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Chart v5.2 User's Guide Book

1. A P PEN DI X C Technical Notes Calculation Details Depending on your data it may be useful to know the mathematical details behind some of Chart s analysis functions in order to get the best use out of them This appendix gives details of the algorithms used by the Spectrum window the Derivative channel calculation the Digital Filter channel calculation and the Smoothing channel calculation The Spectrum Window FFT Physical phenomena can be described in terms of time or its inverse frequency The functions describing a phenomenon in the time domain or frequency domain are effectively equivalent and one can switch between them using certain linear transforms Spectrum uses a discrete Fast Fourier Transform FFT algorithm to convert data from time to frequency domains Spectrum divides the data into segments with the number of data points in each segment equal to a power of two a requirement of the algorithm this is the FFT size shown in the Spectrum Settings dialog Once a selection made in the Chart View is divided up into segments of this size the transform is applied to each segment to calculate its spectrum The spectrum plotted is the average of these partial spectra Averaging improves the amplitude accuracy over a large selection If the number of data points selected does not divide up exactly into a whole number of FFTs and the selection is unadjusted Use Current is Chart Software Z
2. E V Refer Toolbar Buttons p 204 Figure 2 9 The Toolbar the Start button is not shown Record Monitor Button The Record Monitor button at the bottom right of the Chart View to the left of the Start button controls whether data are recorded as they are sampled the default or merely displayed and discarded when sampling stops When monitoring to get an idea of incoming signal characteristics perhaps a cross is shown Click the button to switch between recording and monitoring Scroll Review Button The Scroll Review button is at the bottom right of the Chart View to the left of the Compression buttons When it is depressed data are scrolled while recording the normal behavior When it is raised you can use the Scroll bar to review the recorded data even during recording Pointer The pointer will change form as you move it about the Chart View giving you an indication of its function in certain areas it becomes an beam over a text entry area for instance The Toolbar The toolbar provides shortcuts for common tasks in Chart in the form of a row of buttons The button functions are indicated if the pointer is held over them Toolbar buttons can be hidden and shown again through the Menus dialog Go to start Auto scale Open Print Zoom View Data Pad of file all channels E sHs amp oii El Mm 3 New Save to disk Chart View XY View Data Pad Go to miniwindow end of file 34 Chart
3. Line graticule Y Hide O Dot graticule Always seconds When the time gets large enough in the Chart View and always in the Data Pad it is displayed in hours minutes and Chapter 4 Data Display 83 V Refer Displaying Digital Read outs p 9 Figure 4 5 A recording comprising a series of short blocks Lines between blocks displayed Se eee No display of lines between blocks V Refer Printing Comments p 126 seconds unless the Always seconds checkbox is selected in which case the time is displayed in decimal seconds Display date When this checkbox is selected the date display appears to the right of the Comments bar in the Chart View window If the pointer is over the data display area or Time axis the Date display shows the date at which the data points tracked by the Waveform Cursor were recorded Even if the checkbox is deselected and no display appears the date can still be shown in a DYM miniwindow General Display By default all the display control checkboxes are selected and active Click a checkbox to toggle it off or on and so disable or reinstate a particular feature Lines between blocks Normally Chart draws a solid vertical line between user defined blocks of data to indicate some form of discontinuity such as sampling being stopped and then restarted an input being turned off or the sampling rate being altered You can turn off this control and have no
4. Copyright and Trademarks PowerChrom and e corder are registered trademarks and EChem is a trademark of eDAQ Pty Ltd Chart and Scope are trademarks of ADInstruments Pty Ltd and are used under license All eDAQ software hardware and documentation is protected by copyright eDAQ retains the exclusive ownership of the trademarks and registered trademarks represented by its company name logo and product names Responsibilities You and any others using any eDAQ product agree to use it in a sensible manner for purposes for which it is suited and agree to take responsibility for their actions and the results of their actions If problems arise with an eDAQ product eDAQ will make all reasonable efforts to fix them This service may incur a charge depending on the nature of the problems and is subject to the other conditions in this Agreement Hardware Warranty eDAQ Pty Ltd warrants PowerChrom 280 and e corder systems to be free of defects in material and workmanship for one year from the date of purchase eDAQ Pty Ltd will repair or replace defective equipment as appropriate To obtain a warranty repair replacement you must first notify us before return of the instrument and we will issue you with a RAN return authorization number You must ship the defective product at your Licensing amp Warranty expense We will pay return shipping The product should be packed safely preferably in its original packaging an
5. The available formats in the Save as type drop down list for Chart data are Chart data file settings file and text file You can also save the contents of the Data Pad as a text file or an Excel file or save the contents of the Spectrum window as a text file Other formats such as WAV audio file QuickTime movie and MATLAB file can be added by Chart extensions You can save multiple copies of a file in any format or formats if the copies have different names or are in different places You can even save while sampling at slower sampling rates Data File The data file format the default saves both data and settings including macros The file chronicles the entire recording and is the usual way to save data Settings File The settings file format does not save any recorded data but stores the current settings These include those that affect recording such as the sampling rate input ranges triggering and stimulation settings and those that affect the way the data looks such as the window size channel areas display settings and menu layouts Units macros Notebook text and Data Pad arrangements are also stored as settings Using settings files you can build up a library of settings for many different experiments to enable quick and easy preparation for recording Double clicking on a settings file icon or opening a settings file using the Open directory dialog will create a new untitled Chart file with all the setting
6. is selected For convenience each table below shows a group of related shortcuts Menu Commands Action Select all data in the window Copy to Clipboard Add information on selection to Data Pad Find and select data matching user criteria Find and select next data matching user criteria Set Selection dialog Add comment Comments window New Open Print Start stop macro recording Save tile Auto Scale all channels Paste Paste Chart data at right end of Chart docu ment Cut selection Channel Settings dialog Undo last action Undo the undo Close the active window Shortcut Ctrl A Ctrl C Ctr D Ctr F Ctr F3 Ctr J Ctr K Ctr L Ctr N Ctr O Ctr P Ctr R Ctr S Ctrl U Ctr V Ctrl Shift V Ctr X Ctr Y Ctr Z Ctr Shift Z Ctr F4 Delete selection Delete Appendix A Menus amp Shortcuts 225 Cycle through open windows making each Ctrl F6 active in turn Exit Chart Alt FA Open Chart Online Help F Navigation Action Shortcut rape oe Scroll lett or right Lett or right arrow Chart navigation shoricuts Go to start or end of file Ctrl lett or right arrow Go to a comment Double click comment in Comments window Data Selection Table A 3 Set active point in a channe Click in channe Chart data selection l l o l horicuii Set active point over all chan Click in Time axis nels Select area in a cha
7. 85 V Refer The XY View p 147 Figure 4 8 Line styles and colors The Color drop down list for the graticule gives a choice of thirteen colors or more if your system is set to 16 bit color depth or greater it is the same as the Color drop down list for the XY View see Figure 4 8 Choose the Line graticule or Dot graticule radio buttons to show graticules as solid lines or dots in the Chart Zoom and XY Views I Tin Style drop down list Color drop down list Channel Settings The Channel Settings dialog lets you set up multiple channels conveniently you can both see and specify recording and display settings for each channel in the one place To open the dialog choose Channel Settings from the Setup menu or type Ctrl Y Note that when there is no e corder connected the hardware settings from Range to Computed Input are blank and unusable In the previous chapter the columns in the dialog are summarized and most of the recording settings are discussed in detail In this chapter most of the display settings are discussed in detail 86 Chart Software Figure 4 9 The Channel Settings dialog Channel Settings 10 Input Amplifier Raw Data Input 1 5y v Input Amplifier He Raw Data Input 2 Cyclic Measurem Derivative Channel 6 200 mY Input Amplifier m Raw Data Input 6 No Calculation v Channel 7 2 mY Input Amplifier Raw Data
8. Each Repeat macro command you specify should be paired with an End Repeat If you do not specify enough End Repeats they are automatically added when you select Stop Recording but if you have a complex macro the repeated sequences might not end up in the right places Writing down the macro before recording it will help to avoid such problems Wait While Sampling The Wait While Sampling macro command is used any time after sampling starts and suspends macro steps that follow it until sampling stops For example you might want to start recording apply some stimuli which must be done while sampling record the results for a time and give the user the choice to start another cycle of stimulation or stop the macro using a macro message You would need the message box to appear only after sampling had stopped not immediately after the stimulus so macro steps would have to be suspended at that stage Essentially the Wait While Sampling command allows refinement of the options given in the Macro Sampling dialog Figure 7 12 which only allow you to suspend or continue with all other macro steps while sampling Stop Sampling The Stop Sampling macro command is used to stop Chart sampling Choose it from the submenu at any stage in a macro to provide a user stop the Start button doesn t actually start Chart sampling while you record a macro so the Stop button does not appear In some circumstances if you switch back and forth
9. command 165 Cyclic Minimum computed input function 193 D data acquisition 13 20 data buffering 41 42 Data Buffering dialog 42 Data Buffering command 41 data display area 33 49 channel areas 78 splitting 78 79 data file 24 114 data limit area 188 data linking 107 109 data loss 14 40 42 102 127 186 Data Pad 104 135 147 adding data 90 138 adding data while sampling 138 block information 143 compacting data 140 different block units 138 functions 139 144 limits 135 OLE Linking 108 printing 121 145 Recalculate command 145 Replace Row with Current Values command 137 Reselect Data command 144 saving 145 saving as text file or Excel file 114 setting up 139 140 source data for rows 144 145 time format 139 using as spreadsheet 137 146 147 Data Pad Column Setup dialog 140 Data Pad command 135 Data Pad miniwindow 141 data resolution 78 data selection 98 101 Date display 84 Date miniwindow 92 dates of recordings 83 Default Document Settings dialog 200 default settings 200 Default Settings command 200 Define Unit dialog 58 defining units 58 Delete Macro dialog 209 Delete Macro command 209 Delete Unit dialog 59 deleting units 59 Derivative channel calculation 170 172 calculation details 241 Derivative dialog 171 Derivative command 170 differential stimulus 73 Index 267 time derivative 169 195 Differential computed input func
10. Chart version 5 2 for Windows 2000 XP e corder www DAQG com This document was as far as possible accurate at the time of printing Changes may have been made to the software and hardware it describes since then though eDAQ reserves the right to alter specifications as required Late breaking information may be supplied separately Trademarks of eDAQ e corder and PowerChrom are registered trademarks of eDAQ Pyy Ltd The names of specific recording units such as e corder 201 are trademarks of eDAQ Pty Ltd EChem is a trademark of eDAQ Pty Ltd Chart and Scope are trademarks of ADInstruments Pty Ltd and used by eDAQ under license Other Trademarks Apple Mac and Macintosh are registered trademarks of Apple Computer Inc Windows 2000 and Windows XP are either registered trademarks or trademarks of Microsoft Corporation All other trademarks are the properties of their respective owners Document Number UM ES200W 0105 Copyright January 2005 eDAQ Pty Ltd 6 Doig Avenue Denistone East NSW 2112 Australia Web www eDAQ com Email support eDAQ com All rights reserved No part of this document may be reproduced by any means without the prior written permission of eDAQ Pty Ltd Chart Software 1 Getting Started 7 Learning to Use Chart 8 Where to Start 8 How to Use this Manual 8 Product Intention 9 Computer Requirements 10 The e corder System 10 First Us
11. Digital Filter V Refer The Digital Filter channel calculation provides six types of filter low Filtering p 15 pass high pass notch narrow band pass band pass and band stop The filters work both online and offline V Refer In many ways the calculation offers more flexibility than the filtering The Input Amplifier options in the Inout Amplifier p 50 e You can specify any cut off frequency and transition width subject to practical limits The Low pass drop down list in the Input Amplifier dialog has only a finite number of selectable cut off frequencies and you cannot specify the transition width of the filter High pass filtering available using the AC coupled checkbox in the Input Amplifier is specifically designed for removing DC offset and has a single cut off frequency e Digital Filter works offline which means that you can record at the highest sampling rates and then filter later Filters available in the Chapter 6 Data Analysis 173 Figure 6 24 The Digital Filter dialog with the available filter types shown Input Amplifier work online only which means that they use a significant amount of the e corder s processing power and therefore can limit maximum sampling rates Choosing the Digital Filter command from a Channel Function pop up menu displays the Digital Filter dialog for that channel As with most channel calculations you specify a source channel in the Source channel drop dow
12. Space Bar Esc key Ctrl or Ctrl Shift 1 Double click in channel Click in the channel type in text then Enter type in text then Enter Double click Marker or click Marker box Click in the Time axis Appendix A Menus amp Shortcuts 22 7 Windows Table A 6 Select deselect adjacent items in list Shift click in list Useful Windows shortcuts Select deselect separate items in list Ctrl click in list Change focus change active control for Tab instance move between text entry fields in dialogs Accept OK dialogs Enter Cancel dialogs Esc key There are many other Windows shortcuts of course See the system help for details For instance you can press the Alt key to activate menus use the left or right arrow key to select a menu and the down arrow key to show it You can also more directly press the Alt key and then type the underlined letter in the menu title to show it The menu commands also have underlined letters often the first letter you type that letter to choose the command in an active menu This also works to activate controls with underlined letters in dialogs etc You can also use the up and down arrow keys to select and highlight a menu command and then press the Enter key to choose activate it 228 Chart Software A PP EN DI X B Troubleshooting Technical Support Chart has been extensively tested to make
13. f Contact Closure External Trigger Options Choose Edit gt Preferences gt External Trigger Options to open the External Trigger Options dialog the dialog is also available from the Trigger dialog You can choose whether the e corder external trigger input responds to a voltage level or to a contact closure The Current State icon shows red when the trigger is activated and shows Ex otherwise Special Access It is possible to change menu preferences so that vital menu commands are locked or menus themselves hidden Use the Special Access dialog which appears on typing either Ctrl the backslash character or Ctrl Shift 1 Chapter 7 Customizing amp Automating 205 Figure 7 8 The Special Access dialog Special Access Menu Editor Default Settings Data Buffering Clicking the Menu Editor button accesses the Menus dialog letting you show hidden menus unlock menu commands and otherwise alter settings Click the Default Settings button to access the Default Document Settings dialog It lets you save the current settings in the file including menu layouts etc as those Chart uses when it starts up This is useful when you use Chart for routine work requiring the same settings day after day It also means that exiting and restarting Chart will not face the user with a Chart file that could have quite different settings and none of the safeguards you may have set up Clickin
14. replace the recorded data in a channel and can be used in channels that have their inputs turned off They may be online you see the results as you sample or offline you see the results of the calculation only after sampling finishes Number of Channels ee eee This control at the bottom of the dialog lets you choose the number of channels displayed in the Chart View Click or press the up or down arrows to increment or decrement the number the up and down arrows on the keyboard also work when the control is active or type a value in the text box directly The lower channels are hidden first The control s text entry box is highlighted when the dialog is first opened so that you can just type a number and press Enter to quickly change the number of channels used by Chart 62 Chart Software Figure 3 11 The Trigger dialog Triggering Triggering determines the way Chart starts and stops recording A trigger is an event such as clicking the Start button or a voltage above some preset threshold in an incoming waveform To set up triggering choose Trigger from the Setup menu the Trigger dialog Figure 3 1 1 appears You can use the controls to set up the type of trigger event you want the delay until recording the duration of recording how many times to repeat triggering etc By default the Stop control is set to User controls not used under these conditions are hidden or appear dimmed Choose the sour
15. then release the mouse button You can do this while recording I my ja M Start Rd r jiii Eee 1 1 k You can use the Scroll bars of the two panes to scroll through the two views of recorded data independently keyboard scrolling commands control the right hand pane Double clicking the Split bar or dragging it as far left as it will go returns it to the off position at the left of the data display area and leaves you with a single pane once more The Amplitude Axis The scale of the vertical Amplitude axis of each channel can be independently shifted stretched compressed or set exactly for optimum data display Scale appearance options can be selected from the Scale Chapter 4 Data Display 79 zl te 2na e i fee na d 4 fal e Auto Scale Single Sided Bipolar Invert Scale and Data Set Scale Figure 4 3 The Set Scale dialog pop up menu the button for which is located at the top left of each channel s Amplitude axis Each axis also has Scaling buttons and the axis can be dragged in various ways These Amplitude axis features are also available on the vertical and or horizontal axes of the Zoom View XY View and the Spectrum window You can also auto scale the axes in all channels simultaneously This also works in the Zoom View Scale Pop up Menu Options Auto Scale This option scales the waveform currently visible in the channel to fit it vertically to the display area the
16. Chart Software Figure 6 2 Measuring relative waveform data Marker not in block A Not Valid To set the reference point drag the Marker into the channel of interest it will lock onto the waveform there when you release the mouse button Watch the changing numbers in the Rate Time and Range Amplitude displays to help to select a data point If you need finer control of where the Marker ends up use the Zoom View to look at a selection in more detail the Marker is duplicated there and can more easily be assigned to a particular data point If there is a selection in the Chart View you can choose commands from the Set Marker submenu of the Commands menu to locate the Marker where you want it Minimum Point Maximum Point First Point or Last Point The Marker is then moved to the lowest highest left most or right most points in the selection respectively either in a specific channel or the top one if several are selected If there is an active point in the Chart View any of the commands moves the Marker to the position of the active point Once the Marker is in position measurements relative to it preceded by A are given in the readings for time in the Rate Time display as the pointer moves Figure 6 2 The reading in the Range Amplitude display for the channel where the Marker is located is also relative to the Marker but the values at the Waveform Cursor positions for the waveforms in other channels are absolute
17. OK when you have chosen an icon and typed in the message Repeat While In Block This macro command allows you to perform some operation while the selection or active point remains within a block of data You should specify an End Repeat command after the instructions you want performed in the repeated sequence For instance you may want to find all the peaks from the start to the end of a block of data and record their heights in the Data Pad You would make use of the Find command for this 1 Choose Start Recording from the Macro menu 2 Choose Find from the Commands menu and set up the Find and Select dialog Go Start of this block Set active point OK 214 Chart Software Figure 7 17 The Repeat Select Every dialog 3 Choose Repeat While In Block from the Macro Commands submenu a Choose Find again and set up the Find and Select dialog for the search Find Data Next button Local Maxima Set active point OK Choose Add to Data Pad from the Commands menu Choose End Repeat from the Macro Commands submenu Choose Stop Recording from the Macro menu CON O ON Name the macro and assign a keystroke if you wish Repeat Select Every This macro command allows you to select sequential periods of data in a Chart file and to perform some operation on them When you choose the Repeat Select Every macro command a dialog appears Figure 7 17 allowing you to set a selection period wi
18. Once copied to the Clipboard data can be pasted into another application such as a word processor or spreadsheet which will use the data in its preferred form as text in a word processor say or as a bitmap in a painting program or an object group in a drawing program Using an OLE Link means that the pasted data will reflect changes to the data in the Chart document Pasting Chart Data as Text You can copy data from the Chart View the Data Pad or other windows such as the Zoom or XY View to other applications as text If the Chart View is active and you select an area of data Copy Chart Data and Cut Chart Data are available in the Edit menu When different windows are active the Copy command in the Edit menu changes to indicate the options available If the Data Pad is the active window then you can copy all of it or selected rows to the Clipboard as text When you paste the Chart data into an application that expects text such as Microsoft Word or Excel Chart displays the Convert Chart Data to Text dialog Figure 5 8 This allows you to control the following aspects of the appearance of the data 104 Chart Software Figure 5 8 The Convert Chart Data to Text dialog Convert Chart Data to Text Channels lilzlsletslelzte Always Seconds Channel settings Comments Out oF range data Clip out of range data values Output NaN For out of range data values Reduction 2 Link bound to selection U
19. There is also the Control menu common to all Windows applications indicated by the icon to the left of the rest of the menus Some of the menu commands shown will change or be disabled depending on the active window and what if anything is selected If you hold the pointer over a menu command text describing its function appears in the Status bar at the bottom of the Chart Application window this text is also shown beside each menu command in the figures below An ellipsis after a menu command indicates that it opens a dialog a check to its left indicates that it is currently active and a keyboard shortcut if there is one is shown to its right Restore the window to its previous size Mowe Move the window to another position using arrow keys Size Change the size of the window using arrow keys Minimize Reduce the window to an icon O Maximize Enlarge the window to its maximum size b close Alt F4 Close the window Chart Software 221 Figure A 2 The File menu Figure A 3 The Edit menu Experiments Gallery Mew Open Append Close Save Save 45 Save Selection Page Setup Print Preview Print Chart Views 1 CProgram Files 4D0Instrument Functions edcht 2 CProgram Files 4D0Instrumen I Open the Experiments Gallery dialog Ctrl M Create a new document Ctrl o Open an existing document Append data settings trom another tile Close this document Ctrl s Sav
20. displays are updated every quarter of a second or so Blocks and Settings A solid vertical line is drawn by default between two sections user defined blocks of recorded data to indicate discontinuity for instance if you stop recording and then start again If you change the range of one or more inputs a new scale is drawn between the two Chapter 2 Introduction to Chart 35 Figure 2 12 Record Monitor button left data displayed and recorded right data displayed but not recorded blocks to show the new range for each channel Blocks always apply across all channels even if settings on only one have been changed At slower rates you can change the sampling rate and input range settings without having to stop and restart recording Chart will simply start a new block at the point where the settings were changed drawing a solid vertical line or a new scale as appropriate The display will momentarily stop scrolling while you are making settings changes then update once the operation is complete Recording or Monitoring The Record Monitor button at the bottom right of the Chart View to the left of the Start button controls whether sampled data are recorded the default or merely displayed on the screen perhaps to get an idea of incoming signal characteristics When monitoring sampled data can be seen coming in but the data are not actually recorded and disappear once sampling stops Clicking the button
21. each cycle Note that the derivative functions should be used with caution on an unsmoothed signal because of the way in which the derivative accentuates noise in a signal Chapter 6 Data Analysis 169 Vv Refer The Data Pad p 135 Variance The variance function calculates the statistical variance of the data values in each cycle Unit Spikes at Events The unit spikes function displays spikes of one unit in amplitude for each detected cycle Display in the Chart View Once the controls in the Cyclic Measurements dialog have been adjusted click OK to apply the calculation to the display channel in the Chart View The calculated measurement applies to the whole channel Note that displaying cycle markers can markedly slow performance when many cycles are visible in the Chart View Data Pad Functions Cyclic Measurements also adds functions to the Data Pad These functions are similar to those available as channel calculations and are based on the same cycle detection settings The Cyclic Measurements Data Pad functions are discussed in the Data Pad section of this chapter Detection settings made or changed in either the Cyclic Measurements dialog or through the Data Pad are always associated with the source input not the calculation display channel or the Data Pad column Each input has one and only one corresponding set of detection settings Updating the settings from a Channel Calculation or Data Pad column updat
22. if you have made any changes to a document an alert will appear asking you if you wish to save your work Click Yes if you wish to keep the changes you have made Click No if you want to discard the changes Chapter 2 Introduction to Chart 2r Figure 2 5 The Chart Application window with no visible document windows if there are no open documents the Commands and Macro menus and many Toolbar buttons do not appear The Chart Application Window All essential controls for recording data are provided within the Chart Application window and the Chart View These controls are discussed below and where appropriate in greater detail elsewhere The Chart Application window itself contains all document windows Title bar 28 Chart ene File Edit Setup Window Help b ar rin a Gar bel Toolbar 944 1 ME Prog ress bar Status bar Memory indicator The Menu bar at the top of the Chart Application window contains the Chart menus see Appendix A allowing you to set up and modify the way Chart looks and behaves The toolbar provides shortcuts in the form of buttons for common tasks such as opening or saving a Chart file The left panel of the Status bar at the bottom of the window indicates the function of any menu command or toolbar button at which the pointer is pointing The right panel indicates the state of Chart in some cases recording a macro for example A memory indicator and progress bar indica
23. p 156 Spectrum Chart Extensions p 218 Figure 5 13 The Save As dialog ReadText Error Period 0 01 5 An unknown line Format has been encountered This line will be ignored Do you wish to continue loading this File Line 1 should first check your text file in case it s not the file you thought it was Then you should either reimport the text file with the Ignore non numeric lines checkbox in the Open Text File dialog selected This will ignore data headers as well so settings information will not be read in or e edit the text file to remove extraneous material column headings from a spreadsheet or whatever An alert will inform you if no valid data at all were found in the text file Saving Options To save a file of recorded data choose Save from the File menu type Ctrl S or click the Save button in the toolbar When this is done an existing file will have any changes made to it saved to disk The first time that you save a file or whenever you choose Save As from the File menu the Save As dialog appears Save As Save in Demo Files E Functions1 re E Functions2 My Recent Mechanical Vibrations Documents Desktop My Documents 43 My Computer File name My Network Save as type Chart Data File adicht Chapter 5 Working With Files 113 Data File zA Hiz Settings File V Refer Appending Files p 116
24. s Start button or double clicking the program icon or its shortcut from wherever it was installed Chart s default document has been altered e Choose Default Settings from the Edit menu and click the Revert button in the Default Document Settings dialog that appears New Chart documents can then use the defaults originally set in Chart with all channels having a 10 volt range and so on some settings depend on the attached e corder until the default settings are changed again You can customize the settings in the default document yourself and create your own Chart settings files to ensure that you have the settings menus and macros that you want Interface Problems Some data display areas show gray Chart channels show gray if they are turned off while recording or if they are monitoring rather than recording Most dialogs and windows require a selection of data in the Chart View to display a waveform The Zoom View needs a selection in the Chart View not an active point e Select data in the Chart View if there is no selection The Time axis shows very large or negative values The file with which you are working is an old one with new data recorded in it or one created by appending files or selections and the time is displayed from the start of the record Chart remembers the date and time of all recordings you can choose to display the date if you wish Hence a section recorded before the one at the start of
25. scaled at different factors If the underlying data are valid and you want to make the appearance of the waveform seem more usual then change the display settings y axis stretching and time axis compression not the recording settings sampling speed and full scale input range Ecotm Ecotm Ecotm Econ Chapter 1 Getting Started 19 The screen display most computer monitors is generally about 72 dots per inch dpi so the apparent resolution may be poor if the display is kept small The signal might appear jagged and unresolved on screen However the resolution of the underlying recorded data is independent of the resolution of the display even if the channel display is very thin or not visible on screen sampled data are recorded at full fidelity as can be seen by expanding the display or examining the waveform in the Zoom View Printing can also affect the appearce of your signals In particular high resolution printing can show the selected signal very accurately Because of this a printed signal might not appear as smooth as an old fashioned pen recorder might produce In this case using Chart s Smooth channel calculation or a low pass digital filter to give a more standard looking result It is important to check display settings and axis labels carefully when examining a signal to be sure of what you are looking at especially if the settings on your machine might have been altered A waveform may
26. the basic Print command changes to Print Selection and Save Selection becomes undimmed In the Edit menu Copy Chart Data Cut Chart Data and Clear Selection also become available Chapter 5 Working With Files 99 Figure 5 5 The Set Selection dialog V Refer Time Format p 82 Using Set Selection Choosing Set Selection from the Commands menu opens the Set Selection dialog Figure 5 5 You can keep the dialog open while you work in the Chart View selections made in the Chart View are represented in the dialog and changes made in the dialog are displayed as a selection in the Chart View Set Selection From Start of Block s 4s seconds Active point Block Days Time End 7 o 00 00 50 659 lt gt Duration 00 00 50 232 C Locked Channels 1 Channel 1 w The Set Selection dialog allows you to set the time extent of a selection and the channels involved You can chose the format for the Start and End times at the top of the dialog these options are similar to those of the Display Settings dialog Select the Active point checkbox if you wish to set an active point in the Chart View rather than a selection The End and Duration time controls become hidden the other controls function as described below Time Extent You set the time extent of a selection by specifying the Start time and either an End time or a Duration Depending on the time format selected you can make time block days
27. two downward pointing triangles appear beside the cursor Dragging downward will stretch the scale and dragging upward will compress it keeping the top end of the scale fixed in either case Holding down the Alt key causes the downward pointing triangles to be displayed at all times wherever the cursor is on the scale If the pointer is opposite a number at the midpoint of the scale two upward and two downward pointing triangles appear beside the cursor Dragging upward will stretch the scale keeping the bottom end of the scale fixed and dragging downward will stretch the scale keeping the top end fixed Chapter 4 Data Display 8 Auto Scale All Channels You can auto scale the Amplitude axis in all channels simultaneously by choosing Commands gt Auto Scale clicking the Auto Scale button in the toolbar or using the Ctrl U keyboard shortcut This scales the data currently visible in each channel so that the upper limit of the scale is set to the value of the highest peak and the lower limit to the value of the lowest trough Returning to the Original Scale When the scale is altered the numbers indicating the scale in the Amplitude axis of the channel are changed to suit Double clicking in the Amplitude axis area returns the scale to its normal unstretched position with zero at the mid point of the axis Double clicking again toggles between this Bipolar display which has zero in the middle and the Single Sided dis
28. 111 A column with no units conversion in between columns with unit names should have a single asterisk in it instead for the UnitName TopValue and BottomValue header lines Command Line Options You can control how Chart starts by setting command line options In Windows XP for example you can set up a desktop shortcut to start Chart in a particular way by adding an option to the end of the Target text string right click on the shortcut to open the Properties dialog and look on the Shortcut tab An example might be C Program Files eDAQ Chart Chart5 exe USB Note that the quote marks and the space before the slash character are all required and that case is ignored The available command line options are set out in Table C 1 Option Action ANALYSIS Start Chart without an e corder USB Look for an e corder connected using USB NOUSB Do not look for an e corder connected using USB serial number Start Chart using the e corder connected using USB with the given serial number The ANALYSIS USB and options override but do not change the Startup settings made in Edit gt Preferences gt e corder Startup see e corder Startup p 201 You can add more than one option to the command line if two options conflict then the last listed option takes precedence 252 Chart Software A P PEN DI X D Data Pad Spreadsheet Functions Below is a list of
29. 137 145 Reselect Data command 144 RMS Smoothed computed input function 194 Index afd S sampling rates 14 15 46 and Compression buttons 46 appropriate 14 15 computed input 185 continuous 47 digital filters 47 52 mains filter 53 problems 233 too low 14 Save As dialog 113 Save As command 113 115 Save command 113 Save Document As Text dialog 115 Save Selection dialog 116 Save Selection command 99 115 saving a selection 115 scale moving 79 setting 79 stretching 79 Scale pop up menu 32 79 Scaling buttons 32 81 Scroll bar 30 Scroll Review button 34 38 234 Select All command 99 Select e corder command 74 selecting data 98 101 selection information 142 sensitivity bandwidth 187 Set Marker submenu 223 First Point command 131 Last Point command 131 Maximum Point command 131 Minimum Point command 131 Set Scale dialog 80 Set Scale option 80 Set Selection dialog 100 settings 114 200 settings file 24 114 Setup menu 223 Channel Settings command 59 86 Display Settings command 82 Select e corder command 74 Stimulator command 67 Stimulator Panel command 72 Trigger command 63 Zero All Inputs command 55 Shift channel calculation 180 Shift command 180 shortcuts 225 228 signal conditioning 13 signal input controls 53 single sided display 80 slope 142 slow tracking 188 Smoothing calculation details 244 245 Smoothing channel calculation
30. 34 say This is to force spreadsheets such as Excel to recognize fractional seconds since otherwise they can get it wrong To show times as decimal seconds for use with graphing programs etc turn on the Always Seconds option in the Display Settings dialog The three radio buttons in the Data Recording Mode panel indicate when information is to be recorded If the top one is selected then if there are any data selected in the Chart View information will be Chapter 6 Data Analysis 13 Click fo go to and set Recording options list depends Show or hide Explanation of Figure 6 7 up adjacent columns on selection in lefthand list miniwindow selected option The Data Pad Column Setup dialog Data Pad Column A Setup gt Selection list of the Standard Deviation types of Selection amp Active Point Standard Error doi Comments Number of Points 7 ye Slope Maximum Value available Integral Time at Maximum Block Information Minimum Value Cyclic Measurements Time at Minimum Calculates the mean of the data points in the selection or returns the value at the active point Candice Data recording mode of When any channel is selected Channel 5 rop recording O Only when channel is selected ne data From first selected channel channel selection Compact data ET menu recorded about the channel selected in the Channel drop down list if you have selected an area in Channel 2 information on Channel 3 would st
31. Conversion dialog letting you specify the units for a channel and using waveform measurements calibrate the channel The waveform currently in the data display area of the Input Amplifier dialog is transferred to the data display area of the Units Conversion dialog Use the Pause button to capture any specific signal that you want to use Units conversion will only apply to subsequently recorded signals This is the usual way to set up sampling parameters Display Offset Clicking the Display Offset button causes the Input Offset dialog to appear In the dialog a voltmeter displays the signal currently being measured at an e corder input the input is indicated at the top of the dialog If a transducer or some other external equipment has offset adjustment capabilities you can use this to help see when the device is zeroed A vertical arrow appears indicating the zero point if the offset is large The Average checkbox slows the response of the indicator greatly compensating for fluctuations in a signal This dialog is not a control just an indicator that acts like a voltmeter It should be unavailable when the AC coupled checkbox is selected since AC coupling removes all DC voltage and there would be no offset to measure Pod Scan Clicking the Pod Scan button updates the dialog if it has been left open and a pod a type of amplifier see below has been connected or disconnected The Pod Scan button only appears if that input of th
32. In some recording applications the slope may be used as an approximation to a quantity that cannot be measured directly Chart software offers two main ways of deriving slope information e the Data Pad provides individual numerical values e the Derivative channel calculation displays slope as a time varying signal In all cases the raw signal is sampled and digitized before the slope is determined In measuring the slope it is often important to understand how sampling and digitization work because the slope calculated at each time depends on and is calculated from the neighboring sampled points In particular you should avoid gross over sampling Appendix A Technical Notes 245 Figure C 3 Slope measurement with the Data Pad The slope of the line fitted to the selected points is displayed in the appropriate column of the Data Pad that is sampling at a rate that is much higher than needed for fidelity of the raw signal In the calculation of slope high frequency noise tends to be accentuated You should ensure that the raw signal is as clean as possible and use appropriate low pass filter settings to minimize recorded noise Even with a good raw signal it is usually necessary to introduce some form of smoothing or averaging in the slope calculation The overall effect is that the slope is calculated over a wide time interval or from many points and is less affected by point to point variations Dat
33. Input 7 No Calculation Channel 8 10 Input Amplifier Raw Data Input 8 No Calculation qididadptdat d fafa 4 Number of channels Channel Titles Normally the titles for each channel displayed at the right of the Chart View are Channel 1 Channel 2 etc down from the top You can change the titles if you wish to indicate what you are recording To do this select the text entry box for a channel in the Channel Title column of the Channel Settings dialog and type in a new title to overwrite the default one Text in the text entry boxes can be edited normally If entries are left blank the default titles Channel 1 etc will reappear The length of the title is limited to 21 characters or the number of characters that fit in the text entry box whichever is smaller this ensures the channel titles will display properly Click OK to apply any changes to the channel titles and any other changes to the Chart View Color The Color drop down lists for the channels in the Color column of the Channel Settings dialog let you select the color of the data trace in a channel see Figure 4 8 Chapter 4 Data Display 87 V Refer Selecting Data p 98 Figure 4 10 The Zoom View Style The Style drop down lists for the channels in the Style column of the Channel Settings dialog let you select whether data points
34. Modify Waveform Cursor appearance External Trigger Options Set trigger to respond to voltage level or contact closure 222 Chart Software Figure A 5 The Setup menu Figure A 6 The Commands menu Figure A 7 The Set Marker submenu Figure A 8 The Macro menu Figure A 9 The Macro Commands submenu Setup Display Settings Select number of channels and settings Channel Settings Ctrl Change appearances of other features Trigger Set trigger type and starting stopping conditions Input Simultaneously zero signals with some eDAQ Amps w Stimulator Set up and control stimulator stimulator Panel Control a subset of stimulator options Timed Add to Data Pad Set frequency for adding to Data Pad while sampling Commands 4dd Comment Ctrl K Add a comment to the data at the selected time Set Marker t Place marker within selected data see Figure A 7 Add to Data Pad Ctri D Extract parameters for the selection to the Data Pad Multiple Add to Data Pad Set up repeated adding of parameters Go to Start of Data Ctrl Left Go to start of data Go to End of Data Ctrl Right Go to end of data Auto Scale Ctrl U Auto scale data in all channels Set Selection Ctri J Adjust the parameters of the current selection Find Ctrl F Find and select data according to various criteria Find Next Ctrl F3 Repeat the last find Minimum Point Place the Marker at the minimum point in the selection Hazimim piini Place the Marker
35. Software Figure 2 10 Displays of time and signal amplitude while recording 7 2675 115L Volume Vv Refer General Display p 84 Figure 2 11 Blocks of data left break after stopping and starting right after changing a channel s range Recording To start recording click the Start button at the bottom right of the Chart View The button then changes to Stop click it when you want to stop recording Alternatively you can type Ctrl space bar Display while Recording Chart uses the visual metaphor of a mechanical chart recorder recorded data scroll across the data display area from the right of the window as if the display area were a roll of paper in such a device with new data being drawn at the right and old data moving left This way of displaying data can be changed though so that data do not scroll at all by using the Scroll Review button or so that data are displayed in Sweep mode set in the Display Settings dialog During recording the amplitude of the signal being recorded in the right pane if the window is split is shown in the Range Amplitude display at the right of each channel unless sampling at higher rates If units conversion is being used the value is displayed in the set units rather than as a voltage The time is also shown in the Rate Time display at the top of the channel control area in a form depending on the time display format usually from the start of the block These
36. The A delta symbol before a value indicates it is a difference not a direct reading Derived values in the Data Pad etc take the Marker into account when appropriate Add gemas Time at pointer position 22 alls relative to Marker Marker w so rated a Amplitude at Waveform Cursor position relative to Marker 2 6 mmHg N Absolute amplitude in different channels to Marker The Rate Time display indicates if the pointer is not in the same block as the Marker and if the block has a different scale or different units to the one the Marker is in the Range Amplitude display reads A Not Valid as well Chapter 6 Data Analysis 131 Figure 6 3 The Find and Select dialog If the Marker is dragged to a comment box in the Chart View and released the comment box highlights and the Marker locates itself on the data point recorded when the comment was made either in the channel of a channel specific comment or the top channel otherwise This does not work in the Zoom View Double clicking the Marker or clicking its box at the bottom left of the Chart or Zoom View sends it back to its box at the bottom left of the Chart View Finding Data Compressing the data horizontally with the Compression buttons gives an overview of the data in which you can see longer term trends and tind particular events on a large scale However the events you want to tind may be of smaller
37. The Display Settings dialog From start of block Time is measured relative to the start of each new block of data this is the default setting Time is reset to zero at the start of new blocks of data created by clicking the Start button or using the trigger However when a new block marker is created by deleting data the time axis values to the right of the new block marker are those of the original data recording From start of file Time is measured relative to the start of the file This is useful if you want to know the amount of time lost between sampling being stopped and started again Time of day Time is displayed as the time of day the sample was taken it uses either 12 hour or 24 hour display depending on the settings in your computer This is useful if you want to know the particular time of day that an event occurred Time as UTC This checkbox is disabled unless the Time of day radio button is active If it is selected time is displayed as the time of day the sample was taken with respect to coordinated universal time The difference between local time and UTC depends on the settings in your computer i mum Color drop Display Settings P down list General Lines between blocks Show comments Draw comment lines Draw text labels Time Format From start of File Time of day Time as UTC Cl Always seconds Display date Sampling Scroll right to left O Sweep mode Graticule Vi Show
38. The Print Command The Print command appears in various forms depending on which window is active and whether any selection has been made Clicking the Print button in the toolbar is equivalent to choosing the basic Print command Print Chart View prints the whole Chart file Print Selection prints the selected area in the Chart View If there is no selected area in the Chart View only an active point say then Print Chart View is the available command If you have used the Compression buttons to compress a file horizontally up to 2000 1 then the file or selection will print at the chosen compression When printing the contents of the Zoom View XY View or the Spectrum window the Page Layout dialog appears allowing you to adjust the size location and proportions of the image Drag the image to reposition it on the page the gray border shows where it will go and drag the gray borders of the image to adjust its size If the Keep Shape checkbox is deselected then the image can be reshaped at will Chapter 5 Working With Files 119 Otherwise the image is scaled in proportion to its original dimensions which are those of the window or the dimensions set when the checkbox was deselected When you choose to print from the Chart View Comments window Data Pad or the Notebook window the Print dialog Figure 5 20 appears offering some printing options You can set the number of copies choose your printer in the dro
39. To turn off the windowing functions if none of them are suitable choose None from the drop down list This is most appropriate for a large data selection where data at the edges would be expected to have little effect or for those signals easily distorted by the modulation due to windowing Method If the number of selected data points is greater than the FFT size Spectrum determines the spectra of selected data for successive segments of a particular FFT size and then calculates an average spectrum from these FFTs You can choose from the Method drop down list whether successive windows follow one after another with No Overlap or 50 Overlap of the FFT size the default If a windowing function other than None is chosen the Method of computing the spectrum changes to 50 Overlap Chapter 6 Data Analysis 153 If No Overlap were chosen from the Method drop down list a data selection of 1024 points with an FFT size of 512 points for example would be divided into two segments points 1 512 and points 513 1024 If 50 Overlap were chosen for the same data the segments would change to points 1 512 points 256 768 and points 513 1024 The 50 Overlap option gives a better approximation of the moving average of the selected data by doubling the number of computations and overlapping the windows from which spectra are computed On the other hand the extra calculations take more time and may slow things down appreciably espe
40. Yes then for parts of the data where the sampling rate dictates the cut off frequency you have entered will be altered to fit within these limits If you click No you are returned to the Digital Filter dialog and can modify the cut off frequency to fit within limits Note that if Digital Filter has already been applied and the sampling rate is changed so that the cut off frequency no longer falls within permissible limits then a warning message is not possible and the adjustment is made silently In addition cut off and center frequencies must lie within the absolute independent of sampling rate limits of 0 1 mHz and 100 kHz If values outside this range are entered you will be alerted and they must be changed before applying the calculation Digital Filtering Cut off Frequency exceeds half the sampling rate For new data Proceed with these settings anyway Transition Width There are three options for Transition width also known as filter sharpness or df since this can be a critical parameter in determining both the time taken to do the calculation the smaller df is the longer the calculation takes and the suitability of a filter for a particular purpose Auto adjust means df is set to 20 of the cut off frequency unless this means that the computation is overly intense In this event df is increased so that the filter length see below is no longer than 500 samples to reduce the computation time Set t
41. and they each add they each add extra commands to the the Chart software Do NOT relocate extension files while Chart is running When Chart is installed an Extensions unused folder is also created in the Chart folder Move the extension files between that folder and the Extensions V Refer folder to change the ones Chart will load changes take effect when System Configuration Chart restarts To check which Chart extensions are installed choose Information p 229 the Configuration command from the Help menu to open the Configuration Information dialog and click the Extensions tab 218 Chart Software Software Updates Check for new and updated eDAQ software on our web site at http www edaq com software_dnloads html You need to be registered as an e corder user at the eDAQ website before you can download software When you register you are sent a user name and password and these must be provided when you download software Chapter 7 Customizing amp Automating zI 220 Chart Software Figure A 1 The Control menu this is common to all Windows programs A PP EN DI X A Menus amp Shortcuts Menus The menus shown here are the default settings and your copy of Chart may be set up differently since Chart menus are able to be customized Chart has seven of its own menus File Edit Setup Commands Macro Window and Help more can be added with macros and extensions
42. any Chart channel Choosing the Integral command from a Channel Function pop up menu opens the Integral dialog for that channel Figure 6 27 in which you choose the source channel the type of integral the resetting mode the limits of the integral and the scale with which the integral is displayed Integral Channel 1 Standard Integral w Standard Integral Absolute Yalue Positive Only Negative Onl Integral type Reset type No Reset Timed Reset Reset E ach Cycle Time Constant Deca Event Options Reset By Event Integral limits ee Unit s Scale bottom Unik s a Checkbox to calculate the integral over defined time limits A Scale top Decimal places 2 Suto scale Chapter 6 Data Analysis 177 Figure 6 28 The Event Options dialog Integral Type There are four types of integral that you can select from the Integral type drop down list Standard Integral calculates gt y At where At is the interval between samples Absolute Value calculates gt y At Positive Only calculates y At where y y if y gt O and is zero otherwise Negative Only calculates gt y At where y y if y lt O but is zero otherwise Reset Type Every integral is set to zero at the start of a data block The nature of most data integrals is to increase or decrease continuously It is therefore usually necessary to introduce a resetting mechanism to keep the integrated signal with
43. at the maximum point in the selection First Paint Place the Marker at the first point in the selection Last Point Place the Marker at the last point in the selection Start Recording Ctr4 R Start Stop recording a macro Macro Commands Perform various macro commands see submenu Delete Macro Delete a macro from the current list of macros Wai Pause the macro for a set time Play Sound Set an audible alert using available sounds Message Display a customizable message box Repeat While In Block Repeat an action while selection is within a block Repeat Select Every Select regular periods of data for manipulation Repeat Select Each Block Select each block of data for manipulation Begin Repeat Start a repeat sequence End Repeat Finish a repeat sequence Wait while Sampling Leave remaining macro steps until sampling finishes Stop Sampling Generate macro step to stop sampling Appendix A Menus amp Shortcuts 223 Figure A 10 The Window menu the lowest group lists all the open windows in Chart Figure A 11 The Help menu My i ni d Ola Chart view Zoom view AY VIEW Comments Data Pad Notebook Spectrum DYM New Dakta Pad Miniwindow Cascade Tile Arrange Icons Close All i vibrations Chart View Idle 2 Intensity Chart view Idle 3 pHandT sY View Bring the Chart View to the front Display a zoomed version of the selected data Plot data from one channel against
44. available in five forms each of which is useful for particular purposes Int Integral This the normal integral is simply calculated as the sum of the data points multiplied by the sample interval The integral over time of a signal with equal positive and negative summed values would be zero Int Absolute Value is calculated as the sum of the absolute values of the data points multiplied by the sample interval The integral over time of a signal with equal sums of positive and negative values would be double the sum of the positive values Int Positive Only is calculated as the sum of the positive values of the data points multiplied by the sample interval The integral over time of a signal with positive and negative data points would only include the summed values of the positive data points Int Negative Only is calculated as the sum of the negative values of the data points multiplied by the sample interval The integral over time of a signal with positive and negative data points would only include the summed values of the negative data points Int Reset Each Cycle like the normal integral is calculated as the sum of the data points multiplied by the sample interval The integral over time of a signal with equal positive and negative summed values would be zero This function also however resets the integral to zero every time the original waveform completes one cycle so it is particularly useful for periodic waveforms su
45. be applied to points that are too close to the start or to the end of a data block Such points are represented by a constant value equal to the nearest calculated point Thus with a Window width of 255 the first 128 points of a data block will all have the same calculated derivative and similarly for the last 128 points of a data block Appendix A Technical Notes 24 The Digital Filter Calculation Definitions of f and df For low pass high pass band pass and band stop filters the cut off frequency fo is the frequency or frequencies for band pass and band stop filters where the output amplitude falls to half the input amplitude the 6 dB or quarter power point Transition width df is the frequency range for which the output amplitude is between 1 and 99 of the input amplitude For narrow band pass filters fo is the center frequency At this frequency the output amplitude is at least 99 5 of the input amplitude that is there is no more than 0 04 dB of attenuation df is the frequency range for which the output amplitude is greater than 1 of the input amplitude For notch filters fo is the center frequency At this frequency the output amplitude is no more than 0 5 of the input amplitude that is there is at least 46 dB of attenuation df is the frequency range for which the output amplitude is less than 99 of the input amplitude Limits on f and df The absolute maximum and minimum allowable v
46. be chosen from the Trig submenu of the Functions pop up menu Sin Cos and Tan return the sine cosine and tangent These functions expect an argument in radians ASin ACos and ATan return the arc sine arc cosine and arc tangent that is the angle whose sine cosine or tangent is equal to the given value These functions are the inverse functions of sine cosine and tangent The result is expressed in radians ASin and ACos need arguments from 1 to 1 inclusive since sine and cosine produce no values outside those limits so you may need to scale data to fit DegToRad converts degrees to radians and RadToDeg converts radians to degrees 271 radians is equal to 360 degrees Logarithmic Functions Logarithmic functions can be chosen from the Logs submenu of the Functions pop up menu Log10 returns the base 10 logarithm of a number Ln returns the natural base e logarithm of a number The constant e equals approximately 2 7182818 Exp returns the exponential of a number that is e e raised to the power of the argument The exponential is the inverse function of the natural logarithm Chapter 6 Data Analysis 16 Figure 6 18 Example values returned by the Threshold and Window functions Arguments may be constants or channels Noise Functions Random returns random numbers from a uniform distribution between 1 0 and 1 0 inclusive Gaussian returns random numbers from a n
47. being recorded not necessarily effected Perform all actions to be recorded then choose Stop Recording from the Macro menu or type Ctrl R again to finish The New Macro dialog appears The Menu drop down list allows you to select the menu in which your macro will appear from a list of existing menus By default the macro will be added as a new menu command to the Macro menu You can create a new menu by entering its title in the Menu text entry box the Chapter 7 Customizing amp Automating 207 Figure 7 9 The New Macro dialog V Refer Keyboard and Mouse Shortcuts p 225 New Macro x Select an existing menu to which to add the macro or type the name for Menu a new menu Menu item key Type a name for the macro Assign a keyboard shortcut menu will be added to the right of existing menus in the menu bar unless it already exists The name of the macro should be entered in the Menu item text entry box Each name must be unique in its menu An optional keyboard shortcut can be assigned to the macro as well click in the Key text box and press the keys of the shortcut to enter it in the text box The shortcut is assigned when you click OK Keyboard shortcuts must be either a Function key or the Control key with either a letter or Function key and may optionally include the Shift key as well You could thus have shortcuts such as F1 Shift F2 Ctrl T Ctrl Shift T or Ctrl F8 for instance letters are a
48. between recording and Chapter 7 Customizing amp Automating Zig monitoring or change multiple settings such as input ranges this can result in the recording of very short blocks between the steps of the macro Stopping sampling using this macro command before such steps prevents that problem Chart Extensions Chart extensions are additions to the Chart program that add extra functionality such as file translation capability or analysis and display capability For example the Export MATLAB Extension allows you to save Chart files in a format readable by the data analysis application MATLAB and the Curve Fitting Extension allows you to fit experimental data with non linear mathematical functions of best fit Extensions are separate files that may be downloaded free from the eDAQ website htto www edag com software_dnloads html along with documentation that describes how to use them When Chart is installed the Chart5 folder created on the hard disk by default C Program Files eDAQ Chart5 includes an Extensions folder This folder should not be renamed or moved otherwise any Chart extensions that are installed will not load To install an extension exit Chart and run the installer that was provided or downloaded or place the extension file in the Extensions folder Extensions in the Extensions folder will be loaded when Chart starts up It is unlikely that you will want to use all the available Chart extensions
49. channels will be grayed out if a selected area contains no data if an input was turned off while recording say A message in the center of the grayed area will indicate the problem To remedy a problem select channels for analysis select a suitable area in the Chart View enlarge the Spectrum window or show fewer channels in the window As the pointer is moved over the Spectrum data display area Waveform Cursors track the data for each channel The frequency and amplitude readings at their positions are displayed at the top of the channels spectra Each spectrum is drawn in the data trace color used for the channel in the Chart View You can zoom in on data by making a selection and then either clicking on the Zoom button or double clicking the selection The axis controls are the same as those of the Amplitude axis in the Chart View both axes have a Scale pop up menu and Scaling buttons and you can shift or stretch either axis by moving the pointer over them and dragging On the horizontal axis the stretching compressing pointers work the same way as they do on the vertical axis except that the arrows point to the left or right instead of down or up After zooming or changing the scale return to the default axis scales by clicking the Default Axes button at the top left of the window Spectrum Settings Clicking the Settings button at the top left of the Spectrum window opens the Spectrum Settings dialog where parameters for calcu
50. choosing Arrange Icons from the Windows menu For the ultimate clean up you can close all windows including minimized ones by choosing Close All from the Windows menu DER Fie Edit Setup Commands Macro Window Help ecH amp ile E MA 4 p gt Start Waveforms Chart View Idle SEE Waveforms Zoom View Sel _y 200 fs TKS Channel 1 hd 200 mY Channel 1 x 100 mY zi 3 zi 944 1 MB 94 Chart Software CHAPTER FIVE Working With Files Chart files can be easily accessed with the Experiments Gallery and can be edited printed and saved to disk in various formats This saves you time in collating data and setting up experiments and makes it easy to export data to other applications for further analysis This chapter describes using the Experiments Gallery editing and printing data methods for transferring data to other applications saving settings to allow easy repetition of an experiment appending the data or settings of one file to another opening text files saving data as a text or Excel file and the use of comments Chart Software 95 The Experiments Gallery The Experiments Gallery is a framework that provides easy access to Chart data and settings files as well as any related material such as documentation text files or multimedia files It is particularly useful in a teaching environment as it allows teachers to organize files for differen
51. command 63 triggering 63 67 external 64 67 74 fixed duration 66 level 65 slope 65 threshold 64 triggering event 63 troubleshooting 230 235 Turn Input Off command 49 Turn Input On command 49 turning channels off and on 48 49 U underlying data 158 Undo command 102 units conversion 32 50 54 55 59 61 82 calibration 58 Data Pad calculations 138 typing in values 57 using sampled data 57 58 Units Conversion dialog 55 Units Conversion command 55 using this manual 8 V View Chart 30 34 XY 104 106 147 150 Zoom 88 91 104 106 voltmeter 54 W Wait While Sampling command 217 Wait command 212 Waveform Cursor 90 130 131 205 Waveform Cursor dialog 205 waveforms expected shape 19 stacking 89 superimposing 88 where to start 8 window Index 273 Comments 124 126 Data Pad 135 147 Notebook 156 157 Spectrum 151 156 Window menu 224 X Arrange Icons command 94 Cascade command 93 Chart View command 78 Close All command 94 Comments command 124 Data Pad command 135 DVM command 91 New Data Pad Miniwindow command 141 Notebook command 156 Spectrum command 151 Tile command 93 XY View command 148 Zoom View command 88 XY View 104 106 147 150 printing 150 XY View command 148 7A Zero All Inputs command 55 Zoom View 88 91 104 106 comments 90 Marker 90 overlay 89 Zoom View command 88 274 Chart Software
52. data file are not copied across and the appended file s Data Pad is not appended to the 116 Chart Software Figure 5 16 The File Append dialog File Append Look in Demo Files Functions1 Functions2 My Recent Mechanical Vibrations Documents Desktop My Documents PL My Computer File name ype a file name here My Network Files of type Chart File adicht adiset _ Cancel current file s Data Pad Each appended file is treated as a new user defined block or set of blocks with a solid vertical line drawn in to mark its boundary or a new scale if a input s range is different Units set with units conversion are kept as part of that block Recording settings such as input ranges and sampling rate will be the same for subsequent recording as they were prior to appending the file You can append data files to the currently open file as long as there is enough memory to perform the operation Appending a Chart settings file applies its settings to the currently open tile Display settings are affected immediately and subsequent recordings are made using the recording settings of the appended settings file Chapter 5 Working With Files 117 Figure 5 17 The Page Setup dialog Printing Printing a Chart file or part of it gives you a hard copy of data for use in write ups of experiments reports presentations etc Th
53. data over a specified period a new block is defined and marked by a vertical line unless display settings are set otherwise The time axis values in the new block do not start at zero as is the case when a new block is created by clicking the Start button rather the time values of the originally recorded data are preserved If there is only an active point rather than a selection in the Chart View then pressing the Delete key does nothing and the Clear Selection and Cut Chart Data commands are dimmed To clear all of the data from a particular channel ensure that you have a selection or active point confined to that channel and choose Clear Channel from the Edit menu All data are cleared from that channel and the channel appears gray If the active point or selection in the Chart View extends over two or more channels then the menu command is dimmed and cannot be chosen If you do accidentally delete vital data choose Undo from the Edit menu or type Ctrl Z to undo the action and restore the cleared data or cleared channel In fact Chart can undo and redo a whole series of actions such as sampling cutting and pasting hiding channels etc letting you retrace steps and recover from particular mistakes The Undo and Redo commands in the Edit menu change to reflect what can be 102 Chart Software accomplished If you have saved the file previously then if you close the file without saving changes straight away the file will
54. dialog Figure 3 7 directly choose Units Conversion from the appropriate Channel Function pop up menu You can also click the Units button in the Inout Amplifier dialog or click the Units column in the Channel Settings dialog After you choose the Units Conversion menu command directly the selection in the Chart View is shown in the data display area of the dialog That area appears gray or may contain a message if there is no selection or a discontinuous one over two or more blocks If there is an active point or selection you can choose to convert the units of the selected block or blocks of data otherwise the Selected Blocks radio button is dimmed and can t be chosen If the dialog is opened from the Input Amplifier or Channel Settings dialogs you can convert only the units of subsequently recorded signals you can t convert blocks of data or the whole channel and the dialog appears with the top and bottom radio buttons dimmed Using the Units button in the Inout Amplifier dialog transfers the data shown there to the units conversion data display area Chapter 3 Setting Up Chart 2a Figure 3 7 The Units Conversion dialog Difference button Calibration Voltage New units Units drop Units decimal Value button mode values values down list places Units Conversion for Channel 1 d Difference w Units conversion OF on Point i gt 0 988 y m 130 mmHg Units Difference Al Ae G2 Y s 75 mmHg Dec
55. dialog choose Channel Settings from the Setup menu or type Ctrl Y Note that when there is no e corder connected or when an input is off the hardware settings from Range to Computed Input are blank and unusable The functions of this dialog and the dialogs it gives access to are described briefly below and more fully elsewhere Most of the recording settings are discussed in detail in this chapter and the display settings in the next Click OK to apply the changes and return to the Chart View Chapter 3 Setting Up Chart 59 Figure 3 10 The Channel Settings dialog Channel Title Channel 1 V Refer Channel Titles p 87 Input Sethngs Channel Settings a ea en ang rg ac LU CV LRAT A CT Channel 1 X Raw Data Input 1 Channel 2 X Input Amplifier He Raw Data Input 2 Channel 3 Channel 4 Channel 5 Derivative aida 4 4 Channel 6 Raw Data Input 6 No Calculation Channel 7 Input Amplifier Channel 8 Input Amplifier 4 Raw Data Input 7 No Calculation 4 Raw Data Input 8 No Calculation Number of channels 3 H On The checkbox lets you turn the corresponding input for a channel off deselected or on selected It is equivalent to selecting the Turn Input Off or Turn Input On menu commands from the Channel Function pop up menu for a channel If an input is off its recording s
56. display the FFT as lines bars or connected points The Waveform Cursor will track the left edges of bars when these are displayed Connected Points E aldia Remove zero frequency component This option removes the zero frequency value that is the DC offset or the average value of the original data from the data before the spectrum is calculated The checkbox is selected by default since the zero frequency component often has the largest amplitude of all components in a spectrum and is usually unimportant Click the checkbox to deselect or select it Chapter 6 Data Analysis 155 Figure 6 15 The Notebook window Printing and Copying When the Spectrum window is active the print option in the File menu changes to Print Spectrum and if the command is selected the contents of this window rather than the Chart View are printed The Spectrum window can also be copied as a picture for pasting into other applications by choosing Copy Spectrum from the Edit menu Saving as Text To save the Spectrum window contents as a text file choose Save As from the File menu and then choose Spectrum Text File from the Save as type drop down list in the Save As dialog The text file contains two columns separated by tabs one column for frequency and one column for the height of the spectrum at that frequency The Notebook Window The Notebook window is like a laboratory notebook it lets you make detailed note
57. edge effects If a windowing function is used the original data are multiplied by the windowing function w k to weight them N 1 ya X w k h e rikn N Wavy O 240 Chart Software Four of the more useful windowing functions have been provided in Spectrum as shown in Figure C 2 there are many others as discussed in Reference 2 To compensate for the attenuation due to a windowing function when one is in effect all power values P n calculated as shown earlier are multiplied by a factor N Fw k Zero padding If Spectrum s internal data selection is not a multiple of the chosen FFT size the data size is extended to the right by padding it with zero values Windowing functions are applied to the true data before its length is extended by zero padding The Derivative Calculation First Derivative The first derivative or slope at each point is calculated by least squares fitting of a straight line y a bf to all points within the smoothing window Then dy dt b is the returned value Second Derivative The second derivative at each point is calculated by least squares fitting of a parabola y a bt c to all points in the smoothing window Then d y di 2c is the returned value This calculation is performed using the Savitzky Golay method Press et al page 245 End Effects Each derivative value is calculated from a range of preceding and following sample values The calculation cannot therefore
58. ee A So 2 4 Show comments Draw comment lines Draw text labels off E 2 Draw comment lines Draw text labels off 4 Show comments off Draw text labels on Draw text labels The comment text is usually shown alongside a comment line This control turns it off and may be useful if the comment text is obscuring data Sampling The radio buttons in the Sampling panel allow you to change the way sampled data are plotted on the screen When the Scroll right to left option is selected the default data scrolls continuously from the right to the left of the data display area When the Sweep mode option is chosen data are drawn from left to right as they are recorded much like an oscilloscope A vertical line moves left to right across the data display area tracking the front edge of the advancing waveform as it is drawn on screen As with Scroll right to left mode the speed at which this occurs is a function of both the sampling rate and the horizontal compression Aan The Graticule The graticule the display grid can be changed for the Chart and Zoom Views Note that the graticule is displayed in the Zoom View for one or multiple stacked channels but not for multiple overlaid channels since they could have different amplitudes Choosing the Hide radio button from the Graticule panel of the Display Settings dialog turns off the graticule in all three windows Chapter 4 Data Display
59. except when the Persistence slider value is infinite If the window needs redrawing as a result of a scale or window size change for example replotting points may take considerable time if the selection or Persistence setting is large To avoid tying up Chart for long periods the plot stops redrawing after a few seconds in this case and Chart asks you whether you want it to continue drawing Printing and Copying When the XY View is active the print option in the File menu changes to Print XY View and if the command is selected the contents of this window are printed rather than those of the Chart View To copy an XY View in graphical form ensure that the window is active and then choose the Copy XY View command from the Edit menu The copied image can then be pasted into a graphics or wordprocessing document 150 Chart Software V Refer The Spectrum Window FFT p 237 Figure 6 12 The Spectrum window The Spectrum Window The Spectrum window can calculate and display various power or amplitude spectra of selected data The power or amplitude spectrum shows the intensitry of the various frequency components in a signal These power or amplitude spectra are calculated using the discrete Fast Fourier Transform FFT algorithm to convert data from the time domain to the frequency domain Technical details of the algorithm are in Appendix C page 237 Settings Default Zoom Channel Number button Axes button b
60. file is called EDQ tmp where is an identifier assigned by the operating system Chart keeps track of it in another file If the Regularly update disk buffer checkbox in the Data Buffering dialog is selected then blocks of data are written to the buffer file every 60 seconds when sampling This may stop sampling at higher rates if the system cannot cope with demand In the case of a problem that terminates sampling Chart only loses the last minute of recording The rest is stored in the buffer file When Chart runs it searches for a buffer file If it finds one an alert box indicates that the file being recorded prior to the problem needs recovery since it will not have been saved properly In most cases the buffered data should be recoverable If you choose to delete the data it will be lost Note that only recorded data will be recovered and settings not part of a saved file will be lost If the Regularly update disk buffer checkbox in the Data Buffering dialog is not selected then performance will be better In the unlikely event that Chart itself crashes the operating system should still write the sampled data to the buffer file where it should be recoverable If there is a power failure or operating system crash though then the chances are that the data will be lost Once recording has finished you still must save the file using the standard Save command When a file is saved all the buffered data are written to
61. from the supplied text CODE text Returns a numeric code representing the first character of the supplied string COLUMN reference Returns the column number of the supplied reference COLUMNS range Returns the number of columns in a range reference CONCATENATE text1 text2 Joins several text strings into one string COS number Returns the cosine of an angle COUNT value_list Returns the number of values in the supplied list COUNTIF range criteria Returns the number of cells within a range which meet the given criteria COUNTA expression_list Returns the number of non blank values in the supplied list DATE year month day Returns the serial number of the supplied date DATEVALUE text Returns the serial number of a date supplied as a text string DAY serial_number Returns the day of the month that corresponds to the date represented by the supplied number ERROR TYPE error_ref Returns a number corresponding to an error EVEN number Rounds the specified number up to the nearest even integer EXACT expression1 expression2 Compares two expressions for identical case sensitive matches True is returned if the expressions are identical False is returned if they are not EXP number Returns the constant e raised to the specified power FACT number Returns the factorial of a specified number FALSE Returns the logical value False This function always requires the trailing par
62. functions that can be used in formulae entered into Data Pad cells with brief descriptions of each This list is a subset of the functions available in Microsoft Excel More information about how to use them can be found in Microsoft Excel Help The functions are shown below in upper case for clarity but may be entered in the Data Pad in either upper or lower case ABS number Returns the absolute value of a number ACOS number Returns the arc cosine of a number ACOSH number Returns the inverse hyperbolic cosine of a number ADDRESS row column ref_type a1 sheet Creates a cell address as text ANDilogical_list Returns True if all arguments are true returns False if at least one argument is false ASIN number Returns the arc sine of a number ASINH number Returns the inverse hyperbolic sine of a number ATAN number Returns the arc tangent of a number ATAN2 x y Returns the arc tangent of the specified coordinates ATANH number Returns the inverse hyperbolic tangent of a number AVERAGE number list Returns the average of the supplied numbers CEILING number significance Rounds a number up to the nearest multiple of a specitied significance CHAR number Returns a character that corresponds to the supplied ASCII code Chart Software 253 CHOOSE index item_list Returns a value from a list of numbers based on the index number supplied CLEAN text Removes all nonprintable characters
63. interference 19 internal timer 64 interpreting waveforms 19 introduction to data acquisition 13 20 inverted display 80 K keyboard shortcuts 204 225 changing 204 conventions 9 macros 208 L Last Point command 131 Legacy submenu Computed Input command 49 License Manager dialog 201 License Manager command 201 licenses adding 201 deleting 201 entering new Chart 11 line style 61 88 lines between blocks 36 84 linking Chart data to other applications 107 109 M macro commands 212 218 Macro Commands submenu 223 Begin Repeat command 216 End Repeat command 217 Message command 214 Play Sound command 213 Repeat Select Each Block command 216 Repeat Select Every command 215 Repeat While in Block command 214 Stop Sampling command 217 Wait While Sampling command 217 Wait command 212 Macro menu 223 Delete Macro command 209 Index 269 Start Recording command 207 Macro Message dialog 214 Macro Play Sound dialog 213 Macro Sampling dialog 211 Macro Wait dialog 212 macros 206 218 called by other macros 211 changing dialog settings 210 commands 212 218 deleting 209 210 keyboard shortcuts 208 nesting 211 216 playing 209 recording 207 208 sampling 210 saving 207 208 stopping 209 user changes fo settings 210 versions 207 Marker 33 126 130 132 Zoom View 90 Maximum Point command 131 measurement direct 130 relative 130 131 Memory indicator 41 menu c
64. look very strange if it has been stretched vertically and compressed horizontally say 20 Chart Software CHAPTER TWO Introduction to Chart Chart is the application that together with your e corder makes up the e corder system This chapter provides a general overview of Chart looks at the Chart Application window and the Chart View in detail and deals with the basics of recording data Chart Software 21 An Overview of Chart Chart together with the e corder hardware and a computer gives you the capabilities of a multi channel chart recorder and more Depending on your e corder model you can record up to 16 signals on different channels at speeds of 20000 samples s or a single signal on one channel at rates up to 200 O00 samples s page 47 Chart also provides a range of flexible display and powerful analysis features Controls and Display The Chart Application window page 28 and its Document windows page 29 can be resized The data display area can be compressed or expanded horizontally or split into two panes page 78 and the vertical size of each channel can be changed to suit simply by dragging the dividing bars page 78 Inputs for channels can be turned off page 48 and channels can be hidden if they are not required and their amplitude axes can be dragged stretched scaled or set through a dialog for optimum data display page 79 Range page 48 and filte
65. not change this helps to prevent confusion when editing tiles When a file is appended to another file the comments in the appended file remain in the same order but are renumbered following on from the highest comment number in the file to which it was appended Comments in a pasted selection retain their order within the selection and are renumbered in the same way Identifying a Data Point If the Marker is dragged to a comment box in the Chart View the box will highlight When released the Marker will locate itself on a data point recorded when the comment was made If the comment is channel specific the Marker will be located on the waveform of that channel if the comment applies to all channels the Marker will be located on the waveform of the uppermost channel Printing Comments If the Print Comments checkbox is selected in the Print dialog in the Options panel when printing from the Chart View comments are printed following on from the end of the data print out whether you are printing a whole file or a selection If you are printing a selection only the comments that appear in that selection are printed Comments are printed out as a numbered list with the numbers boxed as they are in the Chart View 126 Chart Software When the Comments window is active the print option in the File menu changes to Print Comments and if the command is selected the contents of this window are printed rather than those of
66. or to read long comments To help in searching large files the Channel Number buttons at the top of the window let you choose which channel specific comments appear 124 Chart Software Figure 5 25 The Comments window Demo Comments 12 Wala is We We ie Ws ollie las lia is lie Channel 6 Chanel umber frime fome dS Number butions E 1 z 14 135 3 The comment box also showsthe time fp NE Comment tex NEY E e is editable gt Channel the comment Comment number applies to for all box in the list Comments for channels with highlighted depressed buttons appear by default all of them click to deselect or reselect a channel Comments applying to all channels always appear The Show Times checkbox selected by default shows the times that comments appear in the Time column If you deselect the checkbox then times do not appear and the column is not visible The Time column shows the times in the form set by display settings Column widths can be changed for instance to give more room if comments in the list are obscured Position the pointer on the dividing line in the column header so that it changes into the resizing pointer drag until the column is the desired width a line appears to indicate the new column position then release the mouse button Once a comment in the list is selected by clicking it then it may be edited deleted copied as text or located in the Chart View The p
67. pod connectors These options do not appear where the input for a channel is only single sided in this case the input functions as if the Single sided option were checked permanently Single sided When this option selected only the positive non inverting input on the front of the e corder is used and a positive signal fed into it will be shown as a positive signal on the display The inverting input is grounded Differential When the Differential option is selected both positive non inverting and negative inverting inputs for that channel are used and neither is grounded The signal shown on the display is the difference between the signals at the positive and negative inputs If both input signals were the same they would cancel each other out The Invert checkbox lets you invert the signal on the screen It provides a simple way to change the polarity of the recorded signal without having Chapter 3 Setting Up Chart 33 V Refer Units Conversion p 55 Figure 3 6 The Input Offset dialog Input 1 Offset Average to rewire a circuit or reconnect to the signal source For example you might be recording from a force transducer where an increase in force downwards gives a negative signal but you want to have a downwards force shown as a positive signal on the screen Selecting the Invert checkbox would change the display to do this Other Features Units Clicking the Units button opens the Units
68. regions for band stop filters are generated by subtracting the end effect values for the band pass filter from the input data Choosing df and fp to Reduce Computation Time If the user desires a low cutoff frequency but does not need a sharp transition then the computation time filter length and end effect length can all be significantly reduced simply by choosing a value of df which is greater than 20 of fo The calculation overhead is inversely proportional to df and is greatest when fo gt f 12 so that decimation cannot be used When a sharp transition is required i e a small df reducing fo from above f 12 to below f 12 can decrease the computation time by a factor of three The Mains Filter The mains filter is an adaptive comb filter A template of mains frequency signal present in the input is computed as an ensemble moving average The width of the ensemble is the mains power period typically 16 6 or 20 ms as determined from zero crossings of the mains power The width of the moving average is 64 mains periods The template thus represents components of the incoming signal that were phase locked to the mains frequency during the last 1 second approximately The filtered signal is obtained by subtracting the ensemble average from the incoming signal The Smoothing Calculation The Triangular Bartlett Window An unweighted average is commonly used for smoothing but has the severe disadvantage that it can invert
69. revert to the last version saved You may lose some changes but the data just deleted will be there on reopening the file Transferring Data It may be useful at times to transfer data within Chart files or from Chart to other applications such as a spreadsheet or drawing program Two general approaches are possible e Saving the data as a standard text file which is able to be opened by any application that can import text such as a spreadsheet word processor or statistics package This can be done with a Chart file or selection or the contents of the Data Pad and is described in Saving Options p 113 e Copying selected data from Chart to the Windows Clipboard and pasting it directly to another location either in the same or another Chart file or in a different application When transferring data to another application you may have the option of pasting the data as text or as a picture and of creating a live link between the Chart document and the other application These options are described in the following sections The Clipboard Whenever you cut or copy data from Chart the information or a reference to it is stored on the Clipboard where Windows keeps track of it in memory Should you exit Chart with a lot of material on the Clipboard the material will likely take up a lot of memory so you will be asked if you want to retain it at that stage If not the Clipboard will be cleared Copy Cut and Paste within Cha
70. scale and may not be obvious in such an overview Chart therefore provides another method to find and select data of interest in a recording according to criteria you specify It also helps in automating searching by macros To find data choose Find from the Commands menu or type Ctrl F the Find and Select dialog appears Find and Select Ed ere Channel to Channel direction search Current channel arrows General Go h SPU Find Comment Specific criteria pen criteria Find the next local minimum ignoring minima smaller than the set noise threshold Threshold Hh Expla nation of selected option Selection Set active point Select all channels ieie Ospe 1s Data view Select to previous point S You can set up search and selection criteria as desired to search any channel for comments peaks and troughs in the waveform block boundaries etc and to set the active point at the position found or 132 Chart Software Move by bo seconds Threshold 5 z select data for a period before around or after it for the active channel or all channels Search Criteria You can search for an event in a specific channel or in the current channel the default that is the one with a current selection or active point If the active point or selection in the Chart View extends across multiple channels then the topmost one is searched Use the Channel drop down list at the top left of the dialog to choose the searc
71. separation line between blocks Figure 4 5 This can be useful when you are recording for limited durations at fast sampling rates and so getting very short blocks Show comments The numbered comment boxes dashed line and comment text that appear when a comment is added during or after recording can all be hidden simultaneously by turning this control off This may be useful for printing if you don t want data obscured By default a numbered list of comments is included at the end of a print out anyway with the time marked beside each comment comments can also be printed independently Turning this control off also turns off and dims the Draw comment lines and Draw text labels controls Draw comment lines A dashed vertical line is usually drawn through the data point associated with a particular comment to make location easier Turning this control off may be useful for printing if you don t want data obscured by this line Turning this control off also turns off and dims the Draw text labels control as without the guiding line the oftset of the comment text could be misleading 84 Chart Software Figure 4 6 A recording with comments and various settings v Refer Display While Sampling p 46 Figure 4 7 Sampled data displayed in Sweep mode a vertical line tracks the waveform as it is drawn from left to right Graticule Show Hide V Refer The Zoom View p 88 ie aay
72. slope of the signal in All c calculated by the j Th 7 Derivative calculation with a window width of 5 il r otk ilu NUL bal halk aul e The slope of the signal in c calculated by the Derivative calculation with a window width of 55 Appendix A Technical Notes 249 Figure C 7 A portion of a text file saved from Chart with data header lines and comments Data headers for units appear only if units conversion is used etc V Refer Opening Text Files p 109 Data Headers for Reading Text Chart can read in settings information from a text file together with the data The information is provided through data header lines each of which begins with a keyword such as Interval Range ChannelTitle etc Figure C Interval The Interval data header specifies the interval between consecutive Chart samples the value applies to all channels The reciprocal of the interval should correspond to one of the values in the Default rate drop down list of the Open Text File dialog if not you will be asked to specify a valid rate when importing the file The time unit after the interval must be a valid Chart time unit hr min s ms or ps microseconds A value in the Interval header line overrides information in the first column of the data even if the Times in first column checkbox is selected or a rate was chosen in the Default rate drop down list However if the Times in first column checkbox i
73. step Playing Macro Playing Macro Deleting a Macro To delete existing macros choose the Delete Macro command from the Macro menu the Delete Macro dialog appears Delete Macro Macro Block bo Data Pad Macro Demo El Macro Expt Defaults A scrolling list displays the name of the menu that the macro is in a colon and the name of the macro for all available macros Select the macro to be deleted from the scrolling list and click the Delete button to delete it Shift click or Ctrl click to select several at once for mass deletion Click the OK button to close the dialog and delete the macros you have removed from the list or the Cancel button to ignore deletions As already mentioned macros are part of a particular file and when a file is saved all currently available macros are saved with it When you delete a macro you delete it from memory If the macro is part of the current file it is permanently deleted from that file only when the file is Chapter 7 Customizing amp Automating 209 saved although it will not be available while the file remains open Copies of the macro attached to other files are not deleted Options When Recording Macros Operations involving files and dialogs can be made to behave differently when playing macros depending on whether you want the macro to do the same thing all the time allow user modification etc Changing Dialog Settings Macros can be used to cha
74. sure that it runs smoothly and without difficulties Occasionally however problems may arise and this appendix gives a list of likely solutions If you are experiencing difficulties with Chart that are not covered in this manual or you need technical assistance with your e corder system then eDAQ and its authorized distributors are glad to help You can also visit the eDAQ website www eDAQ com for general information and a list of local offices System Configuration Information In general we will need quite specific information about your hardware and software to help to isolate and to solve problems effectively Since this type of information can be tedious to collate Chart does it all for you Choose Configuration from the Help menu to open the Configuration Information dialog The dialog gives information on which version of Chart is running a detailed description of your computer your e corder and how it is connected special hardware configurations distributor contact information and other information of note in the form of a tabbed dialog Click the various tabs to look at the information under that heading Note that information about standard extensions is not listed under the Extensions tab but is contained in the extended information that is copied to the Clipboard Chart Software 229 Figure B 1 The Configuration Information dialog Configuration Information Chart For Windows v5 2 l Syste
75. switches between recording and monitoring The data display area is grayed while monitoring so it is easy to distinguish monitoring from recording The grayed area disappears along with any sampled data in that area once monitoring stops You cannot add comments while monitoring since there is no real record so the Comments bar is dimmed and typing has no effect You can stop or start recording data into memory at any time during recording by clicking the Record Monitor button This is useful to see if incoming signals are behaving themselves before you actually record them Status while Recording While sampling the Title bar of the Chart View gives information on the recording status of Chart see Figure 2 13 whether data are actually being recorded or whether Chart is waiting for a trigger or for a posttrigger delay time to elapse This gives you a quick visual indication of recording status Recording data means that data are being recorded If data are not being recorded into memory and are only being displayed on the screen Monitoring data shows If you have set up triggering 36 Chart Software Figure 2 13 Title bar while sampling V Refer Comments p 122 Figure 2 14 The Comments bar Document1 Chart View Recording data Documenti Chart View Monitoring data Document1 Chart View Recording post trigger delay Sele Document1 Chart View Recording waiting for t
76. tet Chart Settings File edset Data Pad Only as Text File bet Data Pad Only as Excel File 21s Spectrum Text File tut If you save the Data Pad as text each row of the Data Pad is stored as a row of readings separated by tabs and ending in a return character and the text of the column headings appears at the top of the file Chapter 6 Data Analysis 145 Figure 6 10 Summing columns in the Data Pad Saving the Data Pad as an Excel file generates a normal Excel file with one sheet with the text of the column headings appearing in the first few rows Spreadsheet Functions In addition to all the Data Pad functions available from the Data Pad Column Setup dialog the Data Pad supports a number of standard Microsoft Excel functions When the Cell button is clicked you can enter formulae using these functions into individual Data Pad cells or you can set up a Data Pad column to produce an output based on one of these functions A list of available functions can be found in Appendix D If you save the Data Pad as an Excel file any formulae entered will also be saved To enter a formula in a cell make sure the Cell button is clicked and then select the required cell Use an equals sign at the start of the formula as you would in standard spreadsheet programs You can edit the formula in the editing bar above the column headers If you wish to use the SUM function to sum a column of data and you wi
77. the computer is not tied up doing one thing You do generally need to be using Chart at slower or moderate sampling rates in most cases especially with a slower computer Recording while Reviewing Data Normally when recording in Chart the recorded data scroll across the data display area from the right of the window with new data being drawn at the right and the old data moving left In these circumstances the Scroll bar is dimmed and inactive and the Scroll Review button is 38 Chart Software Figure 2 16 Control changes when reviewing while recording Figure 2 17 Using a split screen You can scroll through Scroll Review button set to Review data already recorded set to Scroll When the button is clicked it highlights and depresses and reviewing becomes active Figure 2 16 When reviewing while recording you can use the Scroll bar to scroll through previously recorded data the scrolling controls all work normally and you can read the Time axis Data are still being recorded but the new data are only visible if you scroll to the right hand end of the record You can select data and thus use the Zoom View XY View Data Pad and Spectrum window and can even print selections while recording You cannot add comments using the Comments bar while reviewing but you can use Add Comment command from the Commands menu instead Recording with a Split Data Display You can split the data display area before o
78. the scale to be displayed in the Scale top and Scale bottom text entry boxes This deselects the Auto scale checkbox This option allows you to adjust the Amplitude axis directly to display a desired range of values just as you can with the Set Scale dialog available from the Chart View The scale will affect the accuracy in significant figures of the displayed numbers Channel calculations in Chart use single precision floating point arithmetic so results are accurate to six decimal places The number of Chapter 6 Data Analysis 179 Figure 6 29 The Shift dialog decimal places set in the dialog from O to 6 affects only the display not the internal accuracy of the calculation Shift Shift is a channel calculation that allows data in a Chart channel to be shifted backwards or forwards in time This can be useful when data have been recorded with a fixed time delay Choosing the Shift command from any Channel Function pop up menu displays the Shift dialog Figure 6 29 for that channel Shift Channel 1 Source channel Channel 1 w As with most channel calculations you specify a source channel in the Source channel drop down list When you click OK the data in the source channel will be displayed shifted to the right or left by the number of seconds entered in the Shift by text box The maximum time shift that can be applied is 10 000 seconds and data can only be shifted by an exact multiple of th
79. tick and show the previously hidden item beside it Clicking an open padlock with a U for unlocked on it changes it to a closed padlock with an L for locked on it and locks the menu command beside it The command still appears in the menu but if it is chosen or its keyboard shortcut typed or its equivalent toolbar button is clicked an alert notifies the user that it is locked and cannot be used Clicking a closed padlock changes it to an open one and unlocks the previously locked menu command beside it Chapter 7 Customizing amp Automating 203 Vv Refer Keyboard and Mouse Shortcuts p 225 V Refer The Toolbar p 34 Figure 7 5 The Controls dialog Keyboard Shortcuts Keyboard shortcuts for menu commands can be added or changed Click a menu command to select it then click in the Key text box Press the keys of the shortcut to enter it in the text box and click the Set button to assign it Keyboard shortcuts must be either a Function key or the Control key with either a letter or Function key and may optionally include the Shift key as well You could thus have shortcuts such as F1 Shift F2 Ctrl T Ctrl Shift T or Ctrl F8 for instance letters are automatically capitalized invalid shortcuts will be rejected If the menu command already has a keyboard shortcut this appears in the text entry box and you can either change it or delete it so that no keyboard shortcut is available If you choose a key
80. time Channel Controls The channel controls are located rightmost in the Chart View at the right of the data display area The Rate pop up menu at the top right of the Chart View controls the sampling rate which must be the same for all channels There are two channel controls for each individual channel Click the down arrow button to the left to choose the range from the Range pop up menu Click the down arrow button to the right of the channel title to choose options from the Channel Function pop up menu Sampling Parameter Display When the pointer is over the channel control area the Rate Time display shows the current sampling rate in samples per second When the pointer is over the data display area or Time axis the Rate Time display shows the time at the cursor position When the pointer is over the channel control area and the channel s input is on the Range Amplitude display shows the current range of each channel When the pointer is over the data display area or Time axis the Range Amplitude display shows the amplitude of the waveform at the cursor position Channel Settings Information Clicking the Channel Information button displays a list of settings that will apply to newly recorded data including the range filter settings 32 Chart Software the e corder input used the sampling rate and details of any channel calculations Click holding in the data display area of a block displays a list of the set
81. to apply the new settings A highlighted area indicates the hysteresis region For a signal to trigger the computed input function it must go above the highlighted area and cross back through it a signal remaining within the region will not trigger the computed function Once the incoming signal is stabilized for cyclic rate and cyclic amplitude functions a threshold and hysteresis should be defined Because the signal is periodic for functions where this applies it doesn t matter in many cases where the threshold is because it will occur in the same place in each cycle It is best to move the threshold if there is a lot of noise around zero though or if the repeating waveform has multiple peaks Valid trigger pulse Hysteresis region Noise Chapter 6 Data Analysis 187 Baseline Tracking OFF Slow Fast Figure 6 35 Applying a sudden change to the input signal at slow and fast tracking speeds Figure 6 36 A square wave left distorted at fast tracking speeds right Baseline Tracking Baseline tracking is used to remove any constant or slowly changing signal from the raw data before computed function triggering occurs In effect it acts as a variable frequency high pass filter ensuring that the threshold and sensitivity settings follow the waveform It works by applying a suitable averaging technique to the raw data and subtracting the result to modify the signal The amount of averaging depends o
82. trick is to choose a low pass filter setting that removes most of the background noise without unduly changing the signal of interest For some signals differential inputs are preferred and can reduce common mode noise due to ground loops Ground loops occur where multiple connected pieces of recording equipment are connected to mains power grounds The e corder single sided inputs are quasi Chart Software Figure 1 10 A signal viewed with various display settings changed this is actually the same waveform in each case differential and automatically neutralize up to a fraction of a volt of ground loop noise the most that normally appears Other important causes of noise are stray electromagnetic and electrostatic fields and include interference often at the mains frequency of 50 Hz or 60 Hz from unshielded power lines switching equipment fluorescent tubes transformers computers network cables VDUs etc The interference can interact significantly with a recorded signal Reasonable care in the arrangement and shielding of equipment and cables will reduce such interference Particularly delicate measurements however may require special apparatus and a controlled environment Actual Display versus Expectations Because the expected shape of a waveform is based on known examples from previous experiments it may be difficult at first to interpret waveforms presented in a new manner especially if they
83. upper limit of the scale is set to the value of the highest peak and the lower limit to the value of the lowest trough This applies even if the signal is very small such as background electrical noise Single Sided This option can be used to view only positive voltage signals It shifts the vertical axis so that zero volts is located at the bottom of the display area Any readings below zero volts will be off the screen to see them select the Bipolar option or drag the scale Bipolar This is the default mode for each channel in Chart It shows both positive and negative signals with zero volts at the center of the vertical scale if no shifting or stretching has been applied Invert This option inverts both scale and signal so that the waveform is flipped vertically about the midpoint of the channel the bottom scale value is shown at the top of the scale and vice versa The menu command is checked if the channel has inversion applied Set Scale This option allows you to adjust the Amplitude axis directly to show the range of values you want It works whether units conversion is on or off When you choose Set Scale the Set Scale dialog for that channel appears allowing you to type in directly the upper and lower limits of the scale to be displayed Set Scale Top mi Units of channel or APER m leftmost visible block 80 Chart Software ta sh oh oh Scaling Buttons The Scaling buttons ar
84. volts not in mV To get a derived value in mV you need to e bracket the sum of the channels and multiply it by 1000 for example Ch1 Ch2 1000 This scales the expression correctly Then e type mV into the Unit name text entry box Cyclic Measurements Cyclic Measurements is a calculation for analyzing periodic waveforms It can be used online as well as offline Cyclic Measurements detects cycles in the waveform and then uses those detected cycles to perform various calculations cyclic minimum maximum mean rate period etc You set cycle detection parameters and choose an output measurement in the Cyclic Measurements dialog Figure 6 19 The dialog is opened by choosing the Cyclic Measurements command from the Channel Function pop up menu of the channel that is to display the results The dialog has controls in five areas and are described here in the order you are likely to use them Chapter 6 Data Analysis 165 Figure 6 19 The Cyclic Measurements dialog Choose the data source here Input Input Choose the channel or input that has the data of interest from the Source drop down list The source data to be measured may be a signal available from an input raw data already recorded in a channel or the result of a channel calculation Cycle Detection Preprocessing Cycle detection preprocessing is used to improve the reliability of cycle detection It has no effect on the calculati
85. when recording a digital pulse Computed Input Controls The Computed Function pop up menu gives the range of available functions Raw Data means the sampled data with no computed function applied and is the default setting The other functions are in related groups cyclic rate Ratemeter Period Frequency and Counter cyclic amplitude Cyclic Mean Cyclic Minimum Cyclic Maximum and Cyclic Height absolute value Abs Smoothed and RMS smoothed envelope Envelope Minimum and Envelope Maximum and calculus Differential and the five forms of Integral normal Integral Int Int Figure 6 37 The Computed Function pop up menu v Haw Data Ratemeter Pernod Frequency Counter Cyclic Mean Cyclic Min Cyclic Max Cyclic Height Abs Smoothed RMS Smoothed Envelope Min Envelope Max Differential Int Integral Int Absolute Value Int Positive Only Int Negative Only Int Reset Each Cycle Absolute Value Int Positive Only Int Negative Only and Int Reset Each Cycle The functions are discussed in detail below The Units and Range controls are available when one of the cyclic rate or calculus functions is selected and the Average control is available when Ratemeter Period or Differential is selected The Time controls are available when one of the integral functions is selected with the exception of Int Reset Each Cycle and the Reset control is available for all of the integral functions Clicking t
86. which appears while a macro is playing changes during a macro wait step to show a progress bar giving a visual indication of wait progress and to indicate the time for which it is waiting Figure 7 14 Playing Macro Waiting For 0 00 40 31 212 Chart Software Figure 7 15 The Macro Play Sound dialog The macro wait feature is useful if you want to perform some steps of an experiment at certain intervals or to record multiple sampling sequences with a specific interval between them Play Sound Choosing the Play Sound macro command opens the Macro Play Sound dialog which allows you to choose from the range of sounds available as files on your computer to set audible alerts in macros It is just a standard Open dialog that opens only sound files Click the name of a sound in the scrolling list to select it To have the selected sound actually played in the macro click the Open button which closes this dialog To choose more than one sound option Shift click or Shift drag to select contiguous sounds in the list or Ctrl click to select or deselect multiple sounds individually Look in My Sounds es My Recent Documents we My Documents 99 My Computer File name BELL e Files of type Wave Files C Open as read only i My Network To save time in creating multiple sounds you can create a library of sound combination macros and sim
87. 0 200 H Raw noise signal sampled at 1 kHz 50Hz low 150Hz high a c m E E Z D Cc 5 r 50 i0 150 200 Hz Hz 50 Hz low pass filter 150 Hz high pass filter 100Hz nbp 3 g 5 E 2 E I E E o T z 0 50 100150 200 0 50 1000C 160 200 Hz Hz 100 Hz notch filter 100 Hz narrow band pass filter 50 150 pass 90 150 stop z a E 5 z z 3 Z Cc T Ez E T 50 100 150 200 0 50 100 150 200 Hz Hz Band pass filter with 50 Hz 150 Hz Band stop filter with 50 Hz 150 Hz low high cutoff low high cutoff frequencies through The type of frequency response you get from each filter type is illustrated in Figure 6 25 Cut off and center frequencies cannot be higher than half the sampling rate and must be higher than 0 00005 of the sampling rate For example if the sampling rate is 1000 s then the maximum cut off frequency is 500 Hz and the minimum is 0 05 Hz When you leave the Digital Filter dialog the software checks the cut off frequency against the sampling rate for existing blocks and new data If you have entered a cut off or center frequency outside these limits then a message similar to that shown in Figure 6 26 appears Chapter 6 Data Analysis 175 Figure 6 26 A cut off frequency limits message box Auto adjust depends on sampling rate Set to 20 of Cut off frequency User defined Transition width 100 Hz Vv Refer The Digital Filter Calculation p 242 If you click
88. 0 points 23s before or during the recording Alternatively you can open the XY View during recording in this case it will appear in front of the Chart View and it will be in Latest mode by default The buttons at the top of the window work as follows When the Selection button is depressed the XY View displays a selection of data if one has previously been made you can make a selection of data while recording by using the Split bar When the Latest button is depressed the XY View displays the latest incoming data the default situation Clicking the Pause button freezes the XY View in its current state clicking it again continues the XY View Clicking the Erase button clears the current XY View The Fade Mode button toggles on and off a mode in which the age of the data points is indicated by the shade new points are darkest and old points are pale The Direction Arrows button toggles on and off a mode in which arrows are drawn on the plot to show the direction of increasing time The Persistence slider controls the maximum number of data points that can be shown in the XY View This number is in the range 8 16 OOO The text above the slider displays the persistence time that corresponds to this number calculated as the number of points divided by the sampling rate with the number of points in brackets At its right hand end the slider value becomes infinite co with this setting points are not removed
89. 1 e corder Startup 201 External Trigger Options command 205 License Manager command 201 Menus command 202 pre triggering 65 Print dialog 121 print preview 118 Print Preview dialog 119 Print Preview command 118 Print command 118 printing 118 121 Chart View 119 commands 120 comments 121 126 Data Pad 145 Notebook window 157 Spectrum window 156 XY View 150 Zoom View 91 Printing dialog 121 problems and solutions 230 235 Progress bar 41 pulse parameters 7 1 Pulse stimulus waveform 68 Q quitting Chart 12 27 R range 17 18 48 53 60 186 189 basics 17 18 choosing 48 Range pop up menu 32 48 Range Amplitude display 32 49 130 131 Rate pop up menu 32 46 Rate Time display 32 35 46 82 130 131 Rate Time miniwindow 91 Ratemeter computed input function 190 raw data 61 186 189 reading text 109 113 data headers 250 252 Recalculate command 145 recently used files 27 Record Monitor button 34 36 recording 22 35 43 changing settings during 36 duration 40 fidelity 20 78 media 41 127 problems 233 234 resolution 18 48 78 running other applications 40 split data display 39 40 while reviewing data 38 with multiple e corders 73 75 Redo command 102 reduction 106 register 12 Register for eDAQ Resources 12 Repeat Select Each Block command 216 Repeat Select Every command 215 Repeat While in Block command 214 Replace Row with Current Values command
90. 1 volt and 30 C gives 3 V say then using the 2 Point Calibration mode you can key in the values left to right top to bottom 1 V 10 3 V 30 Choose C from the Units drop down list and click Apply the data will be displayed in terms of temperature C instead of volts To enter differences in the second row use the Point and Difference mode a delta prefix A in the lower text entry boxes shows that differences rather than absolute values are being used The first row always has absolute values You can set up units conversion using values derived from sampled data Particular data points averages or changes in the waveform in the data display area can be used You can shift and stretch the vertical Amplitude axis to make the best use of the data display area It is the same as the Amplitude axis in the Chart View and the controls function identically If you click in the data display area a vertical line indicates a single point selection and an indicator arrow at the right of the data display shows the point of intersection with the waveform Figure 3 8 If you make a selection in the data display area the indicator arrow at the right of the data display shows the average amplitude of the waveform and two markers above and below it indicate the maximum and minimum data points in the selection Figure 3 8 If there is selected point or area in the data display area then clicking the Value button enters the volt
91. 181 183 Smoothing command 181 software limits 40 software updates 12 special access 205 206 Special Access dialog 206 Spectrum command 151 Spectrum window 151 156 calculation details 237 241 copying 156 printing 156 saving 156 settings 152 155 Split bar 33 39 79 spreadsheet Data Pad use 137 146 147 stacking in Zoom View 90 standby mode 43 Start button Chart View 33 Start drop down list 65 Start Recording command 207 Start time controls 66 startup command line options 252 preferences 201 Startup problems 230 231 statistics 141 272 Chart Software Status bar 28 Step stimulus waveform 68 stimulation continuous 69 differential 73 discrete 69 Stimulator mode 68 Stimulator 67 73 Stimulator command 67 Stimulator dialog 68 Stimulator output 73 Stimulator Panel command 72 Stimulator Panel miniwindow 72 stimulus waveform Pulse 68 Step 68 Stop Sampling command 217 Style drop down list 86 88 system configuration information 229 230 T T connector 74 tear off data displays 91 141 technical support 229 230 text file data headers 250 252 opening 109 113 saving 114 115 threshold and sensitivity 187 Tile command 93 Time axis 31 problems 231 time display controls 82 84 time format 31 35 139 Excel 108 Timed Add to Data Pad dialog 138 toolbar 34 93 204 transferring data 103 109 Trigger dialog 63 Trigger drop down list 63 Trigger
92. 206 Recording a Macro 207 Playing a Macro 209 Deleting a Macro 209 Options When Recording Macros 210 Macro Commands 212 Chart Extensions 218 Software Updates 219 A Menus amp Shortcuts 221 Menus 221 Keyboard and Mouse Shortcuts 225 B Troubleshooting 229 Technical Support 229 Solutions to Common Problems 230 C Technical Notes 237 Calculation Details 237 The Spectrum Window FFT 237 The Derivative Calculation 241 The Digital Filter Calculation 242 The Mains Filter 244 The Smoothing Calculation 244 References 245 Measuring Signal Slopes 245 Data Pad 246 Derivative Channel Calculation 247 The problem of sampling rate 248 Data Headers for Reading Text 250 Command Line Options 252 D Data Pad Spreadsheet Functions 253 E Experiments Gallery Configuration Files 261 Sections 26 Key Lines 262 Comment Lines 262 Example 262 Index 265 Licensing amp Warranty 275 Contents vi Chart Software CHAPTER ONE Getting Started Welcome to Chart for Windows software that combines the familiar simplicity of a strip chart recorder with the powerful analysis features of a digital acquisition system It is part of a range of eDAQ software that provide a multi purpose data recording and analysis environment for use with a computer running Windows 2000 or XP Please note that Chart 5 does not work with Windows Me 98 or earlier versions This chapter contains information on comp
93. 22 Append command 116 Close command 27 Exit command 27 Experiments Gallery command 96 New command 25 Open command 26 Page Setup command 118 Print Preview command 118 Print command 118 Save As command 113 115 Save command 113 Save Selection command 99 115 file size 41 file types buffer 42 data 24 114 Excel 114 Matlab 114 QuickTime 114 settings 24 114 text 109 113 114 115 filtering 15 16 51 53 AC coupled 52 basics 15 16 high pass baseline tracking 188 268 Chart Software low pass 52 mains 52 Find and Select dialog 132 Find Next command 135 Find command 132 finding comments 126 134 finding data 133 finding events 132 135 First Point command 131 Frequency computed input function 192 frequency range 15 Function keys 211 G general display controls 84 85 Go to End of Data command 30 Go to Start of Data command 30 graticule 46 85 86 H Hardware Unavailable dialog 11 Help menu 224 Configuration command 229 horizontal compression 30 hysteresis 187 Information button 32 initial display 48 input amplifier 50 50 55 60 Input Amplifier dialog 50 54 Input Amplifier command 51 Input Offset dialog 54 Integral channel calculation 177 180 Integral computed input function 196 197 Absolute Value 196 Negative Only 196 normal 196 Positive Only 196 Reset Each Cycle 196 resetting 190 197 Integral command 177
94. 5 regional settings Channels The Channel number buttons correspond to the numbers in the default channel titles and are used to decide which channels are to be saved The number of buttons shown is equal to the number of the last channel containing data for example if channels 1 4 and 6 contain data but channels 5 and 7 do not there will be six channel buttons Highlighted depressed buttons indicate which channels will be included in the text by default all visible channels with data Click the buttons to select or deselect channels Channel data will appear as columns in the text in numerical order left to right separated by tabs Time When the Time checkbox is selected the time at which each sample was taken is listed as the first column in the destination file Always Seconds The Always Seconds checkbox is selected by default and causes the time column to be written in seconds format as required by most target applications When the checkbox is clear times are written in hours minutes seconds format Comments When the Comments checkbox is selected comments at any data point are included as the last column in the file If there are no comments in the file then the created text file will have tabs at the end of each line since these would have preceded any recorded comments Deselect the checkbox if you wish to prevent this If the Comments checkbox is the only thing selected a numbered list of comments is saved t
95. 6 123 126 predefined 211 printing 121 126 reading 38 124 show hide 84 truncation 127 Comments command 124 Comments window 124 126 Compression buttons 30 119 and sampling rates 46 Computed Function pop up menu 189 computed input 50 61 197 controls 189 190 functions 190 197 raw data controls 186 189 sampling rates 185 Computed Input dialog box 184 computed input functions Abs Smoothed 194 Counter 192 Cyclic Height 193 Cyclic Maximum 193 Cyclic Mean 193 Cyclic Minimum 193 Differential 195 Envelope Maximum 194 Envelope Minimum 194 Frequency 192 Integral 196 197 Period 191 Ratemeter 190 RMS Smoothed 194 266 Chart Software Computed Input command 184 Computed Input command 184 computer requirements 10 Configuration Information dialog 230 Configuration command 229 constant output voltage 7 1 contacting eDAQ ii 229 Control menu 221 controls and display 22 Controls command 204 conventions 9 Convert Chart Data to Text dialog 105 Copy command 99 104 106 copying Chart data 103 Counter computed input function 192 crashes 235 Cursor command 205 customizing Chart 24 Cut command 99 104 cutting Chart data 103 Cyclic Height computed input function 193 Cyclic Maximum computed input function 193 Cyclic Mean computed input function 193 Cyclic Measurements channel calculation 165 170 Data Pad functions 170 measurements 168 170 Cyclic Measurements
96. Amplitude display Chapter 3 Setting Up Chart 49 V Refer The Input Amplifier p 50 Computed Input p 184 Units Conversion p 55 V Refer Channel Calculations p 158 Input Amplifier opens the Input Amplifier dialog which lets you change input settings apply signal filtering etc and see the effects before recording Computed Input opens the Computed Input dialog box which lets you process signals as they are recorded converting the sampled raw data from any input into computed data The menu command is ticked if the channel has computed input applied Units Conversion opens the Units Conversion dialog which lets you scale or convert the standard voltage reading for a channel into useful units such as mmHg kPa etc and lets you use waveform measurements to calibrate the channel No Calculation when checked means that the displayed data in the channel is the recorded data with no extra calculation applied It is the default setting If a channel calculation has been applied then the menu command for that calculation will be checked The Input Amplifier The Input Amplifier dialog allows software control of the input amplifiers and filters in the e corder itself Each input is set up independently The signal present at an input is displayed so that you can see the effects of changes straight away Signal amplitude Amplitude axis Figure 3 5 Pi Input Amplifier The Input Am
97. Chapter 5 Working With Files 127 128 Chart Software CHAPTER SIX Data Analysis Chart offers a wide range of online and offline calculations and makes it easy to extract parameters and statistics from your data This chapter discusses these analysis options You can measure absolute or relative quantities with the Waveform Cursor and calculate store and export further parameters with the Data Pad You can link Chart data or data in the Data Pad to other applications that support OLE Linking such as Microsoft Excel You can plot data from one channel against that from another either online or offline using the XY View You can arithmetically combine data in different channels smooth data and analyze the cyclic components or the derivatives and integrals of your signals This can be done during sampling or after recording depending on the particular channel calculation applied You can also use the Spectrum window to analyze the frequency components of your data Chart Software 129 V Refer Displaying Digital Read outs p 91 Figure 6 1 Measuring waveform data V Refer Cursor p 205 Measuring from the Waveform When you have finished recording or if you have split the Chart View and are using the left or right pane you can scroll through your data and make measurements directly from the recording since everything is digital you are given a direct read out with no
98. EKDAY serial_number Returns the day of the week that corresponds to the supplied date YEAR serial_number Returns the year that corresponds to the supplied date Appendix A Data Pad Spreadsheet Functions 259 260 Chart Software A P PEN DI X E Experiments Gallery Configuration Files You can customize the appearance of files that are shown in the Experiments Gallery by adding text labels hiding files choosing a default selected file etc This is done on a folder by folder basis by adding a configuration file called labels ini to the appropriate folder The configuration file is a text file containing sections key lines and optionally comment lines see below for an example Note Character case is unimportant for section and key names but is preserved in key values Sections A section starts with a line containing a section name in square brackets and is followed by key lines Most section names consist of tilenames for example Vibration edcht would be the section name for a Chart data file named Vibration and are used to control the appearance of the entry for the file with that name in the Experiments Gallery dialog box The order of the filename sections in the configuration file is the order the entries are shown in the file list Files in a folder that do not have sections in the labels ini file are shown in the file list after the files tha
99. Envelope Maximum still provides information about the maximum values of the waveform These functions could be used for instance to record the maximum and minimum amplitudes of a heartbeat waveform no additional information is gained by sampling these more than once per beat Differential The Differential function gives the first derivative with respect to time of a selected channel s waveform It is useful when the slope or rate of change of a signal is more informative than the raw signal itself For example the volume of fluid in a container could be weighed as it is collected using a force transducer The differential of this plot would give the rate of change of volume that is the flow rate This function is particularly sensitive to noise so the data smoothing provided by the Average control has been extended beyond that offered for Ratemeter or Period functions with a choice of 1 2 4 8 16 32 or 64 preceding samples being averaged Note that this may give rise to a slight phase shift in the waveform Chapter 6 Data Analysis 195 Figure 6 45 Integral the integral of a square wave left is simply a triangular wave right Integral The Integral function measures the area under a waveform calculated as the sum of the data points multiplied by the sample interval You could integrate the signal from an instrument that measures flow rate to calculate volume for instance The integral is
100. Hours Minutes Seconds V Refer Trigger p 63 e Be Hi E Hours Minutes Seconds axis for the time preceding the trigger event which takes place at zero time in some time modes Pre triggering ignores trigger events that occur before the pre trigger time is up rather than starting if a trigger event occurs within that time If you set the pre trigger time to 5 seconds say Chart will sample for 5 seconds before even looking for a trigger The Start time controls are used to set the time before or after the trigger event at which recording starts and are only active when either Post trigger or Pre trigger is selected in the Start drop down list Click the up and down arrows to increment or decrement the numbers or type a value in the text boxes directly If the time set exceeds the limit for pre triggering then when sampling starts it will be reduced to a shorter time and Chart will alert you to the fact Stop You can determine how Chart stops recording using the Stop drop down list User Fixed Duration or End of Trigger When User is chosen recording continues until you click the Stop button or memory runs out the Stop time controls are unavailable When Fixed Duration is chosen recording continues for the set period after the trigger event occurs Note that you must use the Fixed Duration option when Internal Timer is set in the Trigger drop down list otherwise you will get an alert when you try to sample When End o
101. ISLOGICAL expression Determines if the specified expression returns a logical value ISNA expression Determines if the specified expression returns the value not available error ISNONTEXT expression Determines if the specified expression is not text ISNUMBER expression Determines if the specified expression is a number ISREF expression Determines if the specified expression is a range reference Appendix A Data Pad Spreadsheet Functions 255 ISTEXT expression Determines if the specified expression is text LEFT text num_chars Returns the leftmost characters from the specitied text string LEN text Returns the number of characters in the supplied text string LN number Returns the natural logarithm of a number LOG number basel Returns the logarithm of a number to the specitied base LOG10 number Returns the base 10 logarithm of a number LOOKUP lookup_value lookup_range result_range Searches for a value in one range and returns the contents of the corresponding position in a second range LOWER text Changes the textual characters in the specified string to lowercase characters MATCH lookup_value lookup_range comparison A specified value is compared against values in a range The position of the matching value in the search range is returned MAX number_list Returns the largest value in the specified list of numbers MID text start_position num_chars Return
102. PSD power spectral density with units of V2 Hz Power spectral density is calculated as _ _ ptm ae binwidth where bin width is measured in Hz Note that the resolution in the frequency domain bin width depends on the sampling rate 1 A and the number N of points sampled A large value of N increases the error in the estimate of the spectrum A small value of N gives more accurate spectral estimates but with less frequency resolution Appendix A Technical Notes 239 Figure C 2 Windowing functions used by Spectrum and their definitions k is a value between N 2 and N 2 1 where N is the number of sampled points Cosine Bell window Hamming window 0 08 _N 2 0 N 2 1 0 _N 2 0 N 2 1 E 2rk E 27k wka 0 50 1 cos 25 wk 0 544 0 46 cos Z Blackman window Welch window O O N 2 O N 2 1 N 2 O N 2 1 v k 0 42 0 50 cos 228 0 08 cos 48 w k 1 Nay Windowing Functions The FFT assumes that samples represent an integral number of cycles of a periodic waveform The assumption of perfect periodicity can lead to problems If say the first and last values of a waveform seen in the sampling window do not join smoothly together then a spurious frequency reading will be detected at the edge of the sampling window by the FFT this is known as an edge effect Windowing functions reduce the importance of data at the edges of the window used by the FFT thus preventing spurious peaks arising from
103. That Call Other Macros Once a macro has been created it can be used by other macros when it is loaded in memory as a step in the recording of the new macro This enables modular construction of complex procedures Macros can only be nested up to 10 deep however An alert box will appear during the playing of your macros if the combination becomes too recursive and the macro sequence will stop at that stage Chapter 7 Customizing amp Automating 21 Figure 7 13 The Macro Wait dialog showing the three wait modes Figure 7 14 The Playing Macro dialog during a wait step Macro Commands Control structures for macros are provided in the Macro Commands submenu the menu commands are only available while recording a macro They let you provide user feedback using dialogs and sounds set up repeat sequences wait for a certain time etc Wait Choosing the Wait macro command accesses the Wait dialog A drop down list lets you select from three modes e Wait For to wait for a set length of time say 55 seconds e Wait Until to wait until a certain time say 11 20 a m and Wait Until The Next to wait until the next time division say at the next hour before the macro continues Macro Wait e Be BEE Hours Minutes Seconds Macro Wait c Be Bi E Hours Minutes Seconds For example 11 00 00 a m 11 01 00 am and 11 02 00 a m Lx The Playing Macro dialog
104. The e corder Startup dialog that opens Figure 7 3 allows you to set Chapter 7 Customizing amp Automating 201 Figure 7 3 The e corder Hardware Startup dialog which connection types are checked for attached e corders during startup or if you expect to be using analysis mode regularly to turn off e corder detection completely Doing so can significantly reduce the time required for Chart to launch Hardware Unit Startup fx O Always start in analysis mode Search for Hardware Unit gt i Cancel To turn off e corder detection in the Chart startup procedure click the Always start in analysis mode radio button To set which types of connection are checked for attached e corders at startup click the Search for Hardware Unit radio button and check the connection types you require Menus Seven of the Chart menus File Edit Setup Commands Macro Window Help and their commands can be modified from the default settings by using the Menus dialog Figure 7 4 Choose Edit gt Preferences gt Menus to open this dialog You can hide any menu and hide or lock any menu command to create a very simple Chart setup if you want to limit the actions that can be performed This is particularly useful for teaching in a laboratory environment for instance where you might want students to be able to use some features of Chart but not to edit delete or change the data in files The two scrolling lists in
105. There is further material availabl including latest software versions and updates and information on our products from the eDAQ website www eDAQ com Product Intention Please note that products supplied by eDAQ are intended for use in teaching research and industrial applications and environments They are not intended to be used as medical devices or in medical environments Chapter 1 Getting Started 9 A Chart5 for Windows Computer Requirements Basic Computer Requirements e A Pentium level processor e 64 MB RAM for Windows 2000 128 MB RAM for Windows XP e 4O MB free hard disk space e A computer and monitor that support an 800 x 600 256 color display or better e Microsoft Windows 2000 or XP e A CD ROM drive only required for installing the software alternatively a network could be used e A USB interface on your computer The e corder System The e corder system is an integrated system of hardware and software designed to record display and analyze experimental data The system consists of an e corder recording unit and software such as Chart and Scope that run on the computer connected to the e corder Your e corder unit has considerable computing power of its own and performs many tasks that are necessary during data recording Once the e corder transfers the data to the computer the data are available for display manipulation printing storage and retrieval A variety of e corder unit
106. Working With Files 107 to change aspects of the selection such as the start and end points and which channels are included e You can have one or more links from one or more Chart data files into the destination document e You can use the Edit Links dialog choose Links from the Edit menu of a destination application such as Microsoft Word to manage the links into the document The link characteristics that can be edited include the source for the link whether updating is automatic or manual and options for when the application launches Once bound by checking the Link bound to selection checkbox in the Convert Chart Data to Text dialog you can unbind a link from the latest selection by editing the link moniker see below e To Paste Link a Chart selection as a picture and as text into the same Excel document you need to Copy the data selection again but you need not reselect the data and also change one of the settings in the Convert Chart Data to Text dialog e When you Paste Link a Chart selection into Excel you may need to apply a custom format to time data for example hh mm ss 000 where the zeroes indicate decimals for the seconds To link Data Pad rows to another application l Select and copy the Data Pad rows row column range if the Data Pad is in edit mode you wish to be linked to the other application In the destination application position the cursor in Excel select the cell where you want the da
107. a Once an event has been found an active point or selected area is set in the Chart View according to settings made in the lower part of the dialog The Select all channels checkbox is clear by default in which case the active point or selected area set by the command is confined to the search channel Any selected area will extend to the full height of the channel or channels When checked the active point or selection area is set over all channels just as if you had clicked or dragged in the Time axis Choose the Set active point radio button to set an active point at the time of the event Choose the Select to previous point radio button to set a selection area from the time of the event to the nearest boundary of the previous selected area or the previous active point 134 Chart Software If you choose the Select radio button a text entry box and drop down list become enabled Type in a time from O to 100 000 seconds to set the horizontal extent duration of the selected area Choose one of the options in the drop down list After Around or Before After selects an area from the time of the event forwards Before selects an area from the time of the event backwards Around selects an area of data symmetrically around the time of the event The active point or selection area set is shown in the Chart View if it is not visible already You can choose from the Data view drop down list whether the found data are merely vis
108. a and adds parameters for the data to new rows in the Data Pad Multiple Add to Data Pad Selection period o Minutes Seconds Step through whole file Block containing selection O Current selection 4llow partial selections Allows a shorter Final selection if the duration is mot an exact multiple of the selection period Setting Up the Columns The data recorded in the Data Pad will depend on the choices made in the Data Pad Column Setup dialog Figure 6 7 This dialog appears on clicking a column heading and will have the column label A IU in its title To move to the dialogs for adjacent columns and set up many columns quickly click the arrows beneath the dialog title Two scrolling lists let you select from the many forms of information that could be recorded whether derived or direct The left hand list shows the categories of information and the right hand list shows the specific options available in that set The selected option is briefly explained in a box beneath the two lists Some Chart extensions add further parameters to these lists The channel from which data are taken is selected in the Channel drop down list at the right of the dialog Choosing Off in the lefthand list simply turns the column off no data are recorded in it This choice disables the Channel drop down list Note that times in the Data Pad are shown by default with colons and leading zeroes as hours minutes and seconds 0 00 02
109. a Channela Channel 4 Titles Std Dev Mean Max Time Mean 1 1767 0 1576 0 00 00 135 Recorded 1 1783 0 5635 0 00 01 165 O data 1 1548 0 5385 00 00 01 565 1 164 0 4379 O0002 195 The two tools used to deal with data in the Data Pad are chosen using buttons at the top left of the window By default the Row tool is selected and the left button with the pointer like arrow highlighted in this case the pointer is a heavy cross when over the data area Click to select a row Shift click or Shift drag to select contiguous rows the data can then be cleared or cut or copied as tab separated text using the commands in the Edit menu If the Cell button with the A is clicked row numbers are shown in a column at the left of the Data Pad and you can click to select an individual cell just type to overwrite its 136 Chart Software Reselect Data Recalculate Recalculate All Replace Row with Current Values y Add Titles Automatically Add Titles Add Blank Line Unfix Top Row For editing Format Selected Numbers B Channel 1 Standard Deviation A Channel 1 L164 0 165 1 1555 0 0845 1 1397 contents or edit its text by pressing the F2 Function key or typing in the editing bar that appears above the column headings The drop down list to the right of the window has several commands controlling aspects of layout and data selection The Reselect Data Recalculate and Recalculate All commands are des
110. a Pad The Data Pad Slope calculation works by linear regression A straight line y a btis fitted by least squares to all the data points in the selection using a modification of the standard formula given in textbooks of statistics The value of b is then returned as the slope Figure C 3 The amount of smoothing in this value is controlled directly by the number of points in the data selection Slope in Data Pad Chart View Idle KEk Channel A CT Add ikis STIE T Channel OFF aa E E E A a a S E Slope in Data Pad Data Pad Sele A ae ue oe ae oe a SA 85 points from t 8 53 to t 8 614 4 B C Channel 1 Channel 1 Average e Start Hean Slope is Po katana eee ier mY E A m s 21 6439 0049 5035 Selection Wo 00 08 43 a E Start F gt Ee a TE 4 co in oO 246 Chart Software Figure C 4 The Derivative channel calculation dialog If there is a single insertion point instead of a selection two points are used to calculate the slope The least squares slope in this case reduces to a simple formula Jal Xl d 2At N1 where y is the data value after the insertion point y_ is the value before the insertion point and At is the interval between samples Advantage the method of calculation makes the best use of information in the data points Disadvantage values of slope are given only numerically You cannot display t
111. a files with the desired settings or can be applied to existing data files Chart files are also referred to as Chart documents Chart files may have a number of associated windows All have a Chart View in which data is recorded They may also have other document windows that provide alternate views of the data such as the Zoom View XY View or the Spectrum window When a file is opened or closed all its associated document windows will open or close Opening a Chart File It is a good idea to have a Chart file open if you are working through this manual so that you can try the commands controls and settings as they are discussed in the text First make sure that the e corder is properly connected to your computer and is turned on You may wish to learn Chart without the e corder if you have taken home a copy on your portable for instance In this case on starting Chart a dialog Figure 1 2 will offer the Analysis option which lets you use Chart 24 Chart Software Figure 2 2 Chart desktop shortcut double click it to open Chart i PDAQ Chart V Refer The Experiments Gallery pro Figure 2 3 The New Document dialog except for where the e corder hardware is required such as for recording Unusable controls generally appear dimmed You can start Chart with a file by double clicking on the icon of a data file or by double clicking on the icon of a settings file which will open up a new data file
112. a header sets the Chart range for the data It is similar to setting the scale from the Scale pop up menu in the Amplitude axis for a channel It overrides the automatic determination of the data range from the sample values and may clip data values outside that range to those limits if it has been manually altered The range is assumed to be in the units specified by the UnitName data header If there is no UnitName data header then the units are taken as the units specified after the Range header entries and if no units are specified there then the units for each channel are taken to be volts V A column with no range value in between columns with range values should have a single asterisk in it instead for the Range header line UnitName TopValue and BottomValue The UnitName data header turns on units conversion in Chart for each channel corresponding to a column of data with a unit name in this line This is an easy way to change the default units volts of an imported text file Unit names can be anything you like and are not restricted to the unit names available in Chart s Units Conversion dialog The TopValue and BottomValue header lines give information about the maximum and minimum values of units conversion If they are omitted Appendix A Technical Notes 251 Table C 1 Command line options for Chart Chart determines a suitable range automatically when the data is imported see Reading the Text p
113. age value for a single point selection or the average voltage for a selected area in the left box in its row Clicking the Difference button enters the difference between the maximum and minimum of the selection in the left box in its row Differences are indicated by a delta prefix A In each case the right box of the row is then selected so that you can type in the known value in the new units As a shortcut you can double click in the data display area to transfer the data at a point in one step doing this a second time sets the 2 Point Calibration mode and enters data in the unused row Chapter 3 Setting Up Chart oF Value button f Difference button To calibrate a force transducer in a channel for example start recording and apply two known forces to the transducer to get two voltages Stop recording select the area with the two readings and choose Units Conversion from the Channel Function pop up menu for the channel Using the 2 Point Calibration mode select a point or area in the waveform corresponding to one force Figure 3 8 click a Value button to enter its value in a left box and type the known force in the right box beside it Repeat the process for the other force Figure 3 8 entering data in the unused row There may be occasions where you know the relationship between what is measured and the displayed voltage but don t have exact values For example some temperature transducers pro
114. al is too large or small at a particular range choose a more appropriate one Clicking on the right down arrow button at the right of the channel title displays the Channel Function pop up menu giving access to the other channel controls described below 100 mv alll 100 mi E 10y Channel 1 l gt Turn Input Off a4 Input Amplifier ou Computed Input 1 Units Conversion S00 mw 200 mw w Mo Calculation w 100 mw Arithmetic oO m Cyclic Measurements 20 mY Derivative 10 mi Digital Filter 5 mv Integral 2 mi Shift l Smoothing Turning Inputs Off and On In Chart a distinction is made between an input and a channel Input refers to a source of data that could be recorded channel refers to what is displayed in Chart If an input is off then no data is recorded from it Even if an input is on the recorded data may not be visible because it is obscured by a calculation set up on the corresponding channel When Chart starts up with its factory default settings the number of channels which have their corresponding inputs turned on will be the A8 Chart Software V Refer Computed Input p 61 and p 184 V Refer Channel Settings p 59 Figure 3 4 Data display after recording with a channel input turned off the block line shows the discontinuity and the gray area shows where nothing was recorded same as the number of inputs on the connecte
115. ala i T control l T 3 3 p0 100 200 Baseline Tracking Units RESE 2 ee Of Slow Fast Range 200 imin A ange Input Amplifier fioo mi Help Co Carcel 184 Chart Software The Computed Input command from a Channel Function pop up menu is ticked if the channel has computed input applied You can easily check all the channels at once to see the computed function applied if any by looking in the Computed Input column of the Channel Settings dialog box The Computed Input dialog box has two main areas the left side shows the signal display for the raw data similar to that in the Inout Amplifier dialog box and the right shows the signal display for the computed data Initially the right display is gray and few controls appear if something other than Raw Data is chosen from the Computed Function pop up menu then computed input is active the computed signal is shown in the right signal display area and more controls are available Different functions may have different controls Sampling Rates You might have to reduce the sampling rate or turn off channels to sample when using computed inputs since they can use a lot of the e corder s processing power Chart will give an alert if the sampling rate is too high for your setup All computations are done on raw data taken at 2000 samples per second or higher in the e corder and then processed to give derived values at the
116. alues is very large The analog to digital converters ADCs that perform the digitization usually generate a number of values equal to a power of two an ADC with 12 bit resolution can resolve a signal into 2 or 4096 possible amplitude values an ADC with 16 bit resolution can resolve a signal into 2 or 65 536 possible amplitude values The e corder hardware units uses a 16 bit ADC Chart fits 64 O00 of the 65 536 values to the 10 V range allowing some leeway above and below it for signal extremes The values in the10 V range are divided into 64 O00 fixed values from 10 V to 10 V the minimum change in voltage that could be discerned at that range would be 0 3125 mV At 10 mV range the minimum discernible voltage change would be 0 3125 pV Range Range is inversely proportional to gain the amount of amplification and is a more useful concept than gain since it relates directly to the signal being measured The range can be set independently for each input on an e corder recording unit If the signal amplitude exceeds the range there will be severe loss of information This is the same as clipping in a stereo system where music is severely distorted when the amplitude exceeds the capabilities of the amplitier Any signal exceeding the range is out of range a condition indicated where no amplitude can be given If there is any Chapter 1 Getting Started 17 Figure 1 9 Noise in a signal left can mar the or
117. alues of fo are 100 kHz and 0 1 mHz respectively However the realizable filter cut off frequencies depend on the sampling frequency f and are limited to a range from f 20000 to f 2 The minimum transition width df is limited to the largest of either f 20000 or fo 25 while the maximum is f 2 Filter Implementation Low pass and narrow band pass filters are implemented as linear phase Finite Impulse Response FIR filters and designed using the Window Method with a Kaiser window beta 4 86 giving pass and stop band ripple of less than 0 5 Decimation followed by interpolation is used to reduce the calculation overhead when the filter cut off frequency is less than f 12 The other four types of filters high pass notch band pass and band stop are generated arithmetically from one of these two 242 Chart Software types of filter the reason being that this makes decimation practical for all filter types A high pass filter with a given cut off frequency is generated by subtracting a low pass filter output at the same cutoff frequency from the input data Similarly a notch filter with a given center frequency is generated by subtracting a narrow band pass filter output at the same center frequency from the input data A band pass filter is generated by first using a high pass filter at the lower of the two cut off frequencies and then filtering the output with a low pass filter at the higher of the two cut off fre
118. and Chart is unable to find a connected e corder when you click the Scan button then exit the dialog and Chart by clicking the Exit button Chart for Windows Chart is unable to Find an e corder This may be because the corder is turned off or unplugged Y Search for any available recording hardware Continue without the hardware ino recording Exit the application Chapter 1 Getting Started I V Refer Software Updates p 219 Website Resources Registration The first time you run Chart you will also have an opportunity to register your e corder on the eDAQ website Figure 1 3 Clicking the Yes button will launch your default web browser and open the Registration Form on the eDAQ website Completing the form at this point saves you time when you first download an e corder resource If you do not register now you can do so later when you use Check for Updates from the Help menu or by going directly to the eDAQ website at www eDAQ com Register for PowerLab Resources Figure 1 3 Would you like to register For PowerLab Resources Get free access to Register for eDAQ PowerLab Resources such as Software Updates Chart Extensions Extension User Guides Teaching Experiments Application Notes and Resources special offers Exiting Chart If you want to exit Chart after opening a file choose Exit from the File menu If you want to proceed with working through this manual you can leave the file o
119. and date settings in the dialog Time Settings can be adjusted by entering values directly into the text boxes or by using the nudge buttons The nudge buttons alter the seconds component by an increment or a decrement determined by the sampling speed used to record the block and act more quickly the longer you click on the control Block and Days Enter a block number or the number of days 100 Chart Software Figure 5 6 Time controls Figure 5 7 The Channels drop down list Time OO 00 03 406 4 amp Nudge buttons Date Click on the arrow to display a calendar from which to pick a date The calendar only allows you to pick dates on which data were actually recorded Select the Locked checkbox to fix the duration of the selection to a particular value Changing a Start or End time or using the nudge buttons will now slide the selection In the Chart View the cursor changes to a hand icon over the selection which allows you to click and drag the selection Channels You can choose which channels are included in the selection either by selecting from the options in the Channels drop down list Figure 5 7 or by typing channel numbers directly into the text box When you select from the drop down list you can check more than one channel If selected channels are adjacent the channel numbers are displayed as a range for example 2 4 otherwise channel numbers are separated by commas for examp
120. another Ctrl L Display a list of all comments in the file Set up and display parameters for selected data View and or enter notes about the file Display power or amplitude spectrum FFT Display digital time date and channel readouts Display a new Data Pad miniwindow Cascade open windows Tile open windows Line up minimized windows Close all open windows Make the named View or window active Chart Help Fi ADAG Website Chart User Guide Other Manuals Configuration Check for Updates Abouk Chart Launch Chart Online Help Open www eDAQ com in the default browser _ Open Chart software manual requires Acrobat Reader Display the contents of the Documentation folder Show system configuration and status information Check the eDAQ website for updated software Show information about the Chart software Peeeeeeeceveterecererersrerererersrereretsretertretsretscerererrcrrrterrrrrtrrrirrrs 224 Chart Software Table A 1 Chart menu command keyboard shortcuts Keyboard and Mouse Shortcuts Keyboard and mouse actions in general apply to the active Chart document window Keyboard shortcuts for menu commands can be added changed or assigned to user defined actions menu commands are listed alphabetically by shortcut so that you can see at a glance which keys have been used Some of the shortcuts shown will change or be disabled depending on the active window and what if anything
121. are displayed joined by lines or as unjoined dots see Figure 4 8 Just click on the desired line style to choose it The thickness of the line or dot applies only in the Zoom View and not in the Chart View where waveforms are always drawn as one pixel thick lines The Zoom View In the Zoom View you can look at a small section of data in great detail either in one channel or in several channels over the same period of the recording To zoom in on a data selection drag to select an area of interest in the Chart View in the Time axis for multiple channels and choose Zoom View from the Window menu or click the Zoom View button in the toolbar the Zoom View appears Figure 4 10 If there is no selection then the Zoom View will appear gray A large selection will end up compressed History Overlay Stack Time and amplitude readings buttons button button at waveform cursor position Waveforms Zoom View Seles t 105s Channel4 0 3975 V Waveforr Cursor Pointer Marker Tracking channel Identification bars Channel Number buttons 88 Chart Software Figure 4 11 The Zoom View with the Stack button on this is the same selection as shown in Figure 4 10 By default the Overlay button is on and if multiple channels are selected their waveforms are superimposed Waveforms are drawn from the top channel first so the lowest channel in a set will be in front of the rest The numbers of the Channel Numbe
122. ariance as well as a cycle marker Unit Spikes at Events The Scale drop down list allows you to set the top and bottom limits of the Amplitude axis of the channel displaying the Cyclic Measurement results or to have Chart scale the channel automatically Rate Frequency or rate is the number of times that a given event occurs within a certain period The Rate function gives output in beats per minute BPM and is suitable for lower frequency periodic signals such as heartbeats Period A period is the time taken to complete one cycle of a regularly recurring waveform This function determines the period between adjacent cycles in a waveform Period can be more a useful measure than rate or frequency for waveforms with very slow cycles Frequency Frequency is the number of times that a given event occurs within a certain time The Frequency function measures the frequency of the waveform in hertz cycles per second and is suitable for measuring periodic signals of higher frequency than those for which the Rate is used Mean A cyclic mean is the average amplitude of a waveform over a cycle Variations indicate some form of asymmetry The mean function sums the data points of the detected cycle and divides by the number of points This is useful say for determining the displacement in mean 168 Chart Software Figure 6 20 Source top channel and the cyclic mean bottom calculated from it for a block of data blo
123. ase also state e the model and serial number of your e corder unit e the type of computer and operating system being used for example Windows XP or Macintosh OS 10 2 e the software version you are using for example Chart v5 0 2 We endeavor to answer all your questions but in some cases for example where the problem relates to the other equipment that you are using a nominal fee may be charged Jurisdiction eDAQ Pty Ltd is bound by the laws of New South Wales in Australia and any proceedings shall be heard by the Supreme Court of New South Wales in Australia Disclaimer eDAQ reserves the right to alter specifications of hardware and software without notice No liability can be accepted for consequential damages resulting from use of eDAQ products 276 Chart Software Licensing amp Warranty 2 7
124. at it is difficult to decide on a sensible scale setting until you have seen what range the calculated data spans Channel calculations in Chart use single precision floating point arithmetic so results are accurate to six decimal places The number of decimal places set in the dialog from O to 6 affects only the display not the internal accuracy of the calculation Choosing the Window Width Your choice of Window width will most often be made by trial and error In making a choice you should be aware of a bias variance trade off A Window width that is large in comparison with the time span of changes in the signal slope will bias the calculation of the derivative whereas a too small width is likely to give a noisy derivative Figure 6 23 shows a raw signal in the top channel with derivatives calculated by Derivative below using window widths of three five seven 13 and 55 points The derivatives using window widths of three and five points are noisy The derivative using a window width of 55 points is relatively noise free but the peaks are flattened because the window width is comparable with the peak width The derivatives calculated with a window width of seven and 13 points are about right 172 Chart Software Demo Deriv Data Chart View Idle Figure 6 23 A signal and its slope obtained with the Derivative calculation In this example each channel title has been named to show the window width used
125. ata Pad data are usually displayed as text but that from the Chart View can also be displayed as a picture in some applications such as Microsoft Word and Excel To link Chart data to another application 1 In the Chart View select the data you wish to link 2 Copy the selected data to the clipboard by choosing Copy Chart Data from the Edit menu or Ctrl C 3 In the destination application position the cursor in Excel select the cell where you want the data to appear and select Paste Special from the Edit menu 4 In the Paste Special dialog that opens select the Paste link option Choose the format to use for the data the options Picture Unformatted Unicode Text and Text vary depending on the destination application Click OK 5 The Convert Chart Data to Text dialog opens although it may be hidden choose Chart from the Task bar When linking as text you can choose which channels should be included in the link whether or not time comments and channel settings are included and how out of range data are handled The available options are described under Pasting Chart Data as Text p 104 Check the Link bound to selection checkbox if you want the data in the destination document to be updated whenever the current Chart selection changes in some way Note that e When making the Chart data selection you can use the Set Selection dialog choose Set Selection in the Chart Commands menu Chapter 5
126. ata for the corresponding e corder inputs When first turned on higher numbered channels with no matching physical inputs record the Ratemeter computed function based on the raw data of e corder Input 1 The Raw Data Input pop up menu lets you choose any e corder input as the source signal upon which computations are performed Controls are only active if something other than Raw Data is chosen from the Computed Function pop up menu This means that raw data from any e corder input can be processed and the computed results displayed on any channel You can show raw data on one channel and computed data on another to compare them or use several channels to show various computations based on raw data from the same input Note that whenever you record computed data in a channel you replace any raw data that would otherwise have been recorded there so any original signal in that channel would be unavailable for further analysis Clicking the Input Amplifier button opens the Input Amplifier dialog box allowing convenient access to filtering options the display offset and so on for the raw data signal The Range pop up menu lets you select the range of the input to get the best signal response Changing the range in this dialog box is equivalent in all respects to changing it in the Chart View the pop up menu is duplicated here for convenience The Threshold and Sensitivity controls are available when one of the cyclic rate functions Rate
127. ate has been encountered Sampling rate Please select a valid rate bo use instead elas Changing the rate will stretch or compress data with respect to time which may not be what you had in mind If waveform duration and timing are important you should manipulate the data in a spreadsheet or data analysis program through some appropriate interpolation to get data at one of the standard Chart sampling rates Numerous repeated alerts could mean that Chart is trying to interpret data as time values that is the first column contains data points but the Times in first column checkbox in the Open Text File dialog was selected If you think that this is happening stop the procedure check your text file and reimport it with appropriate settings Chart expects data to be in a particular form see page 109 and expects lines not in that form to be data headers with particular keywords giving Chart settings information Invalid lines in the text file will cause an alert to appear Figure 5 1 2 If you choose to continue the offending line is taken to signify the start of a new block but is otherwise ignored Numerous repeated alerts mean that there is a lot of extraneous material in the text file If you have this problem stop the procedure by clicking No in the dialog You 112 Chart Software Figure 5 12 The alert for an unexpected invalid line V Refer Saving as Text or Excel p 145 Data Pad Saving as Text
128. ats This may be useful if you intend to import from the text file into an application that requires U S regional settings Pasting Chart Data as a Picture You can copy data from the Chart View or some other windows such as the Zoom or XY View to some other applications as a picture If the Chart View is active and you select an area of data Copy Chart Data and Cut Chart Data are available in the Edit menu When different windows are active the Copy command in the Edit menu changes to indicate the options available In the destination application position the cursor where you want the data to appear and choose Edit gt Paste Special In the dialog that appears select the Paste option and choose Picture from the list Click OK The picture can then be formatted as required 106 Chart Software Creating an OLE Link from Chart to Another Application Chart is able to act as an OLE server This allows you to link data in a Chart document to another application that can act as an OLE client or controller for example Microsoft Excel or Word OLE links are live or active in that changes to the Chart data as the result of a calculation for example are reflected in the data displayed in the destination document The link can either be independent of later selections in Chart or set up so that the data in the current Chart selection is displayed in the destination document You can use OLE Linking from the Chart View and from the D
129. automatically but remain until you click the Erase button If the window needs to be redrawn the number of points stored is not unlimited but up to a million points can be replotted Note that you can use the up and down arrow keys to increase or decrease the persistence setting in small increments and the Page Up and Page Down keys to increase or decrease it in large increments Note that large dots are drawn much more slowly than the others thin lines are drawn the fastest At very high sampling rates drawing may Chapter 6 Data Analysis 149 be unable to keep up with the new data points which would cause Chart to stop sampling In this circumstance choose thin lines Offline Operation To use the window in offline mode make a selection only the horizontal extent is relevant in the Chart View and then open the XY View The window opens in Selection mode by default Use the buttons at the bottom and right of the window to choose which channels to plot When the Selection button is depressed the data in the selection is shown and the Persistence slider is disabled The Pause and Erase toolbar buttons are also dimmed When the Latest button is depressed a portion at the end of previously recorded data is shown The size of the portion can be varied using the Persistence slider The Pause button is dimmed but you can still use the Erase button to clear the plot The Fade Mode and Direction Arrows buttons are active
130. ber _list Squares each of the supplied numbers and returns the sum of the squares T value Tests the supplied value and returns the value if it is text TAN number Returns the tangent of the specified angle TANH number Returns the hyperbolic tangent of a number TEXT number format Returns the given number as text using the specitied formatting TIME hour minute second Returns a serial number for the supplied time TIMEVALUE text Returns a serial number for the supplied text representation of time TODAY Returns the current date as a serial number TRIM text Removes all spaces from text except single spaces between words TRUE Returns the logical value True This function always requires the trailing parentheses TRUNC number precision Truncates the given number to an integer TYPE expression Returns the argument type of the given expression UPPER text Changes the characters in the specified string to uppercase characters VALUE text Returns the specified text as a number VAR number _list Returns the variance of a population based on a sample of values VARP number _list Returns the variance of a population based on an entire population of values 258 Chart Software VLOOKUP search_item search_range column_index Searches the first column of a table for a value and returns the contents of a cell in that table that corresponds to the location of the search value WE
131. bject to drift with an uncontrolled offset voltage If the raw signal has a DC offset it may take a few seconds for 196 Chart Software Timed Reset E z Figure 6 46 A steady offset and its integral using two forms of resetting the integral to start resetting the speed at which this happens depends on the Baseline Tracking slider setting Resetting helps to compensate for drift that might otherwise take an integrated signal off the scale The Int Reset Each Cycle resets the integral each time the original waveform completes one cycle The other four forms of integral reset the integral as specified in the Reset pop up menu and the Time text box that appear when one these four is the chosen computed input function If No Reset the default is selected in the Reset pop up menu then there is no Time text box If the integral goes out of the set range then it wraps back to zero Choosing Timed Reset in the Reset pop up menu resets the signal to zero after each multiple of the entered time This method copes with drift and computes an accurate integral before the reset Times entered in the Time text box smaller than the sampling interval may round down to zero in which case no resets occur Values should be longer than the interval over which integration is desired in any case Choosing Time Const in the Reset pop up menu introduces an exponential decay so that given a zero input signal the integral dr
132. board shortcut already in use an alert box warns you You have to remove the shortcut from a menu command before reassigning it Appendix A lists Chart s keyboard shortcuts Toolbar Buttons When a menu command that has a toolbar button is selected in the Menus dialog the Show on toolbar checkbox becomes active Deselecting the checkbox will hide the toolbar button for that command when the Menus dialog is closed You can make the toolbar button reappear by selecting the appropriate menu item in the Menus dialog and selecting the checkbox again Controls Choose Edit gt Preferences gt Controls to open the Controls dialog see Figure 7 5 Deselecting the Allow printing of whole file checkbox allows you to disable printing of a whole Chart file without disabling printing altogether This could be useful in a teaching laboratory Controls Allow printing of whole File Cancel 204 Chart Software Figure 7 6 The Waveform Cursor dialog Figure 7 7 The External Trigger Options dialog V Refer Triggering p 63 Cursor Choose Edit gt Preferences gt Cursor to open the Waveform Cursor dialog which presents you with four choices of cursor shape Click a radio button to choose the cursor shape that you prefer and click OK to confirm the choice Waveform Cursor O Square cursor Cancel Hollow target E Target External Trigger Options Curent State Ex Mode f Normal Voltage Level
133. ce Use the text entry box or slider for the trigger event bar to set threshold values Choose the trigger state change up for Trigger positive down for negative Sette staring Sat pevew 8 e E fn f Trigger Document Slope Level condition Hours Minutes Seconds J 0 Be Boom E Set the stopping Hours Minutes Seconds condition BE i B block s External trigger marker ae ep Choose a channel in Set triggering to Use the arrow which to mark an repeat a buttons or text entry external trigger event number of times boxes to set times Setting the Controls Trigger You can choose the event that triggers recording from the Trigger drop down list which gives you the choice of External Trigger Internal Timer User or one of the Chart channels If you select Internal Timer or User Chapter 3 Setting Up Chart 63 e As Bio E Hours Minutes Seconds Chart starts recording when you click the Start button there are no special triggering conditions when it stops depends on the Stop settings If you select one of the other triggering options clicking the Start button gets Chart ready to record the document s Title bar will show the message Recording waiting for trigger and the chosen trigger event then starts Chart recording If Chart is monitoring rather than recording the message will read Monitoring waiting for trigger If you select External Trigger the event comes from an exter
134. chance of the measurement errors that could occur in analyzing a paper and ink record You can make direct or relative measurements When the pointer is over the data display area or Time axis the Waveform Cursor for each channel tracks the waveform at the time position of the pointer Figure 6 1 In this case the Rate Time display shows the time at the pointer location and the Range Amplitude display for each channel shows the amplitude of the waveform at the Waveform Cursor location The Waveform Cursor only gives discrete measurements jumping from data point to data point you can see this more clearly in the Zoom View It cannot provide a reading on the line that is drawn between the points for display purposes Adel f2a5s Time at pointer Pointer RE ne an ae a 39 8 mmHg land Waveform ae a ae ee AtB M Cursor position 3 Amplitude at Wavelon on ea aE Gieei wind T ER ee e GECI Cursor position era The pointer appears as a cross over the data display area or a double headed selection arrow along the Time axis The Waveform Cursor s shape is a cross by default but can be changed in the Preferences submenu of the Edit menu to suit the waveform Using the Marker The Marker can be found in a box at the bottom left of the Chart View It is used to set a particular data point as a zero reference point so that relative measurements can be made with respect to that point 130
135. cially if a windowing function is applied as well and the computer is an older model Selection There are two choices in this drop down list The Use Current option brings the total data points in a selection to a multiple of the FFT size by padding the data with zeroes adding points with a value of zero on the right hand side These trailing zeroes can generate spurious frequencies in strongly periodic data so this option is not always suitable The Adjust to Best Fit option adjusts Spectrum s internal data selection so that it is a multiple of the FFT size by extending symmetrically if possible the data points selected for use within the same block Note that the selection in the Chart View is not altered only Spectrum s internal data selection Display Spectrum can calculate various forms of power or amplitude spectra you can choose which is shown from the Display drop down list In each case the height of the spectrum at a particular frequency is representative of the power or amplitude contained in the waveform at that frequency The Power spectrum and the Amplitude spectrum are basic other forms are derived from them The power in a bin of the spectrum is the modulus squared of the discrete Fourier transform at that frequency The amplitude in a bin is the modulus of the discrete Fourier transform Power and amplitude values are always positive or zero they cannot be negative Power Density and Amplitude De
136. cribed below see Source Data for Rows on page 144 Selecting a row and choosing Replace Row with Current Values allows you to replace those row values with the information on the current selection or active point which is displayed just below the column headings in the Data Pad This allows you to update values in a row by reselecting the row data adjusting the extent of the selection using the Set Selection command for example and then replacing the row values The Add Blank Line and Add Titles commands let you add to the Data Pad either blank lines rows or the current column headings without the column labels as three lines useful to keep track of changed settings or when transferring data to other applications By default the Add Titles Automatically menu command is active a check appears beside it in this case This adds the current column headings to the Data Pad whenever a change is made to the type of data to be recorded The Unfix Top Row for editing command is available when the Cell button is active This lets the top row beneath the column headings scroll out of sight rather than remain fixed and allows you to use the Data Pad as a spreadsheet entering formulae into the top row just as you can in Microsoft Excel and similar programs You can fix number formats by using the Format Selected Numbers command The width of columns can be changed to suit the displayed data and headings You might want to narrow co
137. ctions For convenience the other channel calculations except for Cyclic Measurements which requires more detailed setup are available from the Arithmetic dialog This enables you to quickly combine calculated channels for example you might want to average the derivatives of two channels For the most part these functions work in exactly the same way as they do when accessed from a Channel Function pop up menu Any differences are noted here brief details of required and optional arguments are also given For more details enter these functions with no argument to determine the required syntax and refer to the section in this manual on the equivalent channel calculation function Differentiate is the same as the Derivative channel calculation except that you can choose a derivative order of zero which is equivalent to applying the Smoothing calculation using the Savitzky Golay method and you can choose the order of the fitted polynomial A source channel is required as a parameter optionally followed by window width an odd number from three to 999 derivative order an integer from zero to two and the order of the fitted polynomial an integer from one to five For example Differentiate Ch3 17 2 5 returns the second derivative of Channel 3 using a window width of 17 points and a fitted polynomial of order five By default the derivative order is 1 the order of the fitted polynomial is the same as the derivative order unless the d
138. d To add data parameters to the Data Pad repeatedly while sampling choose Timed Add to Data Pad from the Setup menu In the dialog that appears Figure 6 5 check the Add to Data Pad repeatedly while sampling checkbox and enter a value in seconds to specify the period to be used for each selection Click OK to accept the settings and close the dialog Whenever you now start sampling Chart will repeatedly select the next available period of data and add parameters to a new row in the Data Pad Each new data selection period begins from the end of the previous one Timed Add to Data Pad Selection period seconds ance Multiple Add to Data Pad To add data parameters to the Data Pad repeatedly once data has been recorded choose Multiple Add to Data Pad from the Commands menu In the dialog that appears Figure 6 6 set the period to be used for each repeated selection and choose whether the selections are made from the whole file from the block currently containing the active point or selection or from within a selection You can include data from a final shorter selection by checking the Allow partial selections checkbox 138 Chart Software Figure 6 6 The Multiple Add to Data Pad dialog V Refer Display Settings p 82 Data recording mode When any channel is selected Only when channel is selected From first selected channel When you click OK Chart makes consecutive selections from the dat
139. d e corder These channels will be set to record the raw data from the corresponding inputs The rest of the channels if any will have their inputs turned off and can be used to display channel calculations When inputs for any spare channels that is those not corresponding to an input on the e corder are first turned on they are automatically set to record the raw data from e corder Input 1 This makes use of Computed Inputs and the Computed Input command in the Channel Function pop up menu is checked to indicate this Choosing Turn Input Off from the Channel Function pop up menu turns the corresponding input off The menu command then becomes Turn Input On and if chosen turns the input on again You can also use the On column in the Channel Settings dialog Inputs can be turned off or on while you are recording this creates a new block in the record If an input is turned off the Range Amplitude display is replaced by Input Of The data display areas of channels that have their input turned off appear gray both while recording and afterwards there is neither graticule nor data While an input is turned off the Range pop up menu is disabled Input off a a es Other Functions The other functions in the Channel Function pop up menu are described briefly below and more fully elsewhere Channels with inputs turned off have no Input Amplifier access and show Input Off in the Range
140. d have the RAN on the shipping label Returns sent without a RAN may be refused delivery This warranty does not cover hardware that has e been modified by the user in any way e been subjected to unusual physical electrical or environmental stress This includes damage due to faulty power sockets inadequate earthing or power spikes or surges e been damaged because of incorrect wiring to ancillary equipment or because of substandard connectors or cables or e had the original identification marks removed or altered Software License You have the non exclusive right to use the supplied Chart software Your employees or students for example are entitled to use it provided they adhere to this agreement Each separate purchase of the Chart software licenses it to be used on two computers at any given time on one computer for data acquisition with an e corder hardware unit and on a second computer for the analysis of existing data files Although multiple copies of a program may exist on several computers more than two copies must not be used simultaneously Departmental company licences are available if you wish to run more than two copies simultaneously Chart Software 273 Technical Support Please register your unit to receive technical support Technical assistance is available via email Please describe the problem with as much detail as possible Include a small example data file if appropriate Ple
141. d the Slow submenu Figure 3 2 The graticule with the display at 1 1 it is one division wide Division Setting Sampling Rates You can choose the sampling rate directly using the Rate pop up menu The sampling rate the number of samples per second is shown in the Rate Time display beside it at the top right of the Chart View if the pointer is not over the data display area The sampling rate is the same for all inputs The Rate pop up menu has a submenu which contains slower sampling rates down to a rate of one sample every 10 minutes Note that these slower rates are expressed as an interval between samples rather than as a rate Rate Time display Slow submenu Select a sampling rate Display While Sampling Chart uses the visual metaphor of a mechanical chart recorder normally recorded data scroll across the data display area from the right of the window as if the display area were a roll of paper in such a device with new data being drawn at the right and old data moving left As with the paper in mechanical chart recorders the data display area is marked into divisions by a graticule or grid Divisions are usually 20 pixels wide at any horizontal scale and are marked by the graticule in the data display area they line up with unit divisions on the Time axis The time taken for each graticule division to scroll past depends on both the sampling rate and the horizontal scale set using the Compression but
142. d with that of the settings file Printing When the Notebook window is active the print option in the File menu changes to Print Notebook and if the command is selected the contents of this window are printed rather than those of the Chart View Chapter 6 Data Analysis 157 Figure 6 16 A Channel Function pop up menu hanne Turn Input GFF Input Amplifier Computed Input Units Conversion w Mo Calculation Arithmetic Cyclic Measurements Derivative Digital Filter Integral Shift Smoothing Source channel Channel 1 Channel Calculations The options in the lower half of a Channel Function pop up menu let you choose to apply calculations to channels of recorded data No Calculation is the default setting and means the displayed data in the channel are recorded data with no extra calculation applied The Arithmetic Cyclic Measurements Derivative Digital Filter Integral Shift and Smoothing calculations are built into Chart and are described here Other calculations may be added with Chart extensions Channel calculations may be online you see the results as you sample or offline you see the results of the calculation only after sampling finishes To turn on a channel calculation choose its menu command from a Channel Function pop up menu To revert to the data recorded in a channel if any choose No Calculation A check beside the op
143. de channels You can look at the overall trends in the recording or look at a small section of data in great detail This chapter describes the display options available in Chart from scaling axes through to using the Zoom View and displaying digital read outs Chart Software Figure 4 1 Changing a channel s size drag the channel separator to the desired position and release the mouse button The Chart View As well as the essential controls for recording data many controls to set the display format directly are provided within the Chart View If the Chart View is not active it can be brought to the front by choosing the Chart View command from the Window menu Changing Channel Size To change the size of a channel s display position the pointer over one of the channel separators anywhere along its length so that it changes into the separator pointer Drag the channel separator to the desired position a line appears to indicate where it will go then release the mouse button You can do this while recording 4 C U fa le fa If you drag a channel separator past others it will pick them up for instance if you drag the separator of a channel to the bottom of the data display area in the window you will drag down all those of the channels below it as well Double clicking a channel separator divides the data display area evenly into the number of visible channels as
144. duce a certain change in voltage for a given change in temperature such as A20 mV A4 C If you have one absolute reading at least one of the base values must be absolute such as a calibration value you can use the Point and Difference mode Enter the calibration value in the top row and then select an area in the data display where a known temperature change has been recorded Figure 3 8 Use the Difference button to enter the difference in values in that area in the left box of the other row and type the known change in the right box Choosing Unit Names The Units drop down list lets you choose define or delete units Units are just names and the conversions are set independently so you could have C in two channels say with different conversions Some frequently used units are provided Units are document specitic so defining or deleting them affects only the active document To avoid having to redefine them you can create standard sets of useful units and store them in Chart settings documents or as default settings Choose Define Unit from the Units drop down list to define a new unit The Define Unit dialog appears letting you type in the new unit name its length is limited to the number of characters that fit in the text entry box although long names may be truncated further for display To get unusual symbols for the units such as the degree sign use the Character Map accessory program Start gt Progra
145. e for the End level and Start level controls The available ranges are 200 Chapter 3 Setting Up Chart Zl Figure 3 16 The Stimulator Panel miniwindow mV 500 mV 1 V 2 V 5 Vand 10 V The End level and Start level controls set the exact voltage level for the starting and ending voltages of the step within these ranges The height of each step is then the difference between the End and Start levels divided by the Number of steps set at the top right of the dialog The Stimulator Panel Once you have set up stimulation using the Stimulator dialog you can easily start or stop stimulation or change settings while sampling by using the Stimulator Panel miniwindow Choose Stimulator Panel from the Setup menu fo open if These buttons appear if the stimulus waveform is continuous and stimulation starts when recording starts click to stop or restart stimulation Stimulator Panel Documenti Frequency Pulse duration Amplitude neamen Efrons E woow E ofon This button appears if the stimulus waveform is discrete or if in Manual start mode click to apply stimulus Stimulator Panel Document 1 Number of steps Step width End level sR sooms now E If you choose continuous stimulation and When recording starts in the Start controls then the Panel will have Off and On buttons so you can turn stimulation off or on at will If you choose discrete stimulation or Manually in the Start control
146. e sampling interval Shift rounds the time shift to an integer number of sampling intervals before applying the shift For example if the sampling rate is 200 s Shift will round any time entered to the nearest 200th of a second 5 ms Positive values for the time shift move data to the right In this case a range of data points at the end of each data block is shifted out that is lost from display and the start of each block is padded with the first recorded data value in the block as in Figure 6 30 Negative values for the time shift move data to the left In this case a range of data points at the start of each data block is shifted out and the end of each block is padded with the last recorded data value in the block 180 Chart Software Figure 6 30 Source data in Channel 1 and shifted data in Channel 2 with a shift parameter of 0 5 s Figure 6 31 The Smoothing dialog V Refer The Smoothing Calculation p 244 Shift Demo Chart View Idle Note the padding at the start of the shifted block 0 5 s in this case Smoothing Smoothing is a channel calculation that lets you remove unwanted high frequencies noise or clutter from a waveform It works both offline and online Choosing the Smoothing command from any Channel Function pop up menu displays the Smoothing dialog Figure 6 31 for that channel Smoothing Channel 1 Source channel Channel 1 w Window width paints Smoothi
147. e 10 Basics of Data Acquisition 13 Sampling Rate 14 Filtering 15 Digitization 16 Range 17 Noise 18 Actual Display versus Expectations 19 2 Introduction to Chart 21 An Overview of Chart 22 Chart Files 24 Opening a Chart File 24 Closing a File or Exiting Chart 27 The Chart Application Window 28 Document Windows 29 The Chart View 30 The Toolbar 34 Recording 35 Contents Display while Recording 35 Blocks and Settings 35 Recording or Monitoring 36 Adding Comments while Recording 37 Background Recording 38 Duration of Recording 40 Data Buffering 41 Standby Mode 43 3 Setting Up Chart 45 Setting Sampling Rates 46 Maximum Sampling Rates 47 Channel Controls 48 The Input Amplifier 50 Signal Display 51 Filtering 51 Signal Input Controls 53 Other Features 54 eDAQ Amps and Pods 54 Units Conversion 55 Converting Quantities 56 Choosing Unit Names 58 Channel Settings 59 Triggering 63 Setting the Controls 63 Stimulation 67 Stimulator Mode 68 Setting the Controls 69 Chart Software iii The Stimulator Panel 72 The Stimulator Output 73 Using Multiple e corders 73 Synchronizing Recordings 74 Maximum Sampling Rates 75 4 Data Display 77 The Chart View 78 Changing Channel Size 78 The Split Bar 78 The Amplitude Axis 79 Display Settings 82 Channel Settings 86 Channel Titles 87 Color 87 Style 88 The Zoom View 88 Displaying Digital Read outs 91 Organizing Chart Windows 92 5 Working Wi
148. e Chart View each channel s Amplitude axis can be rescaled offset or otherwise manipulated using the Scale pop up menu Scaling buttons or the pointers that appear when the cursor is over an Amplitude axis Clicking the Overlay button turns off the Stack button and superimposes channel waveforms again Data Display The highlighted depressed Channel Number button indicates the waveform that the Waveform Cursor tracks the active channel whether the channels are overlaid or stacked The time t and amplitude channel title readings at the tracking point are indicated at the top of the window in the forms of time and units set using display settings and units conversion The tracking channel can be changed by clicking one of the undimmed numbered buttons at the bottom of the window or clicking on a different waveform In either case the button of the selected channel will be highlighted depressed to indicate the new tracking channel The Marker from the Chart View is duplicated in the Zoom View moving it onto a waveform in one will do the same in the other double clicking it will send it home etc Its behavior is also similar in the Zoom View although there is a slight difference because the Waveform Cursor only tracks the active waveform if there are several When the Marker rests on the active waveform relative measurements preceded by A are given in the readings for both time and amplitude when the Marker rests on
149. e XY View The XY View displays a plot of data in one or two channel s against data in another over the same period of the recording Figure 6 11 For example you could measure pressure and temperature versus time then use the XY View to graph pressure versus temperature It can also show phase relationships such as between flow and pressure signals The XY View can be used online displaying a plot as data is recorded or offline for the analysis of previously recorded data Selection Latest Pause Erase Fade Mode Direction Arrows Line Style button button button button button button button Figure 6 11 The XY View Document XY View Persistence slider Scale pop up menu Channel 2 Channel Number buttons Chapter 6 Data Analysis 147 V Refer The Amplitude Axis pr V Refer Display Settings p 82 To open the XY View choose the XY View option from the Window menu or click the XY View button in the toolbar The values along the x axis x and y axes y1 left and y2 right at the pointer position are indicated at the top of the window in the units assigned to the channels The XY View always works with the displayed data of the source channels That data may be either the recorded signal or the result of a channel calculation such as Arithmetic or Smoothing The Channel Number buttons on the bottom horizontal x axis and vertical y axes assign the channel to be disp
150. e corders are connected Note that if the e corder is changed for an existing document then settings may be lost if the new e corder has different capabilities such as different filter settings or a lower maximum sampling rate If in doubt about the capabilities of different models make sure the existing document is saved before changing the e corder Documenti Chart View e corder 1621 Idle Select Hardware Select the e corder to use For Documenti e corder 1621 Serial No t 20 0004 connected via USB e corder 201 Serial No plam026 connected via USB Note changing the recording hardware may cause some settings to be lost if the new hardware has different capabilities Synchronizing Recordings You can synchronize the start of recording between multiple documents using an external trigger device connected to the Trigger inputs using T connectors of each connected e corder The synchronization is not exact because of uncertainty in the sampling time this uncertainty is equal to the sampling interval set and uncertainty in the trigger point However provided that the trigger voltage changes rapidly compared with the sampling rate there should only be about one sample interval s difference between different e corders For example with a sampling rate of 10 000 s there should only be a difference of about 1 10 000 0 0001 s If exact synchronization of signals is important to you you should record all y
151. e e corder has a Pod connections input channels 1 4 eDAQ Amps and Pods eDAQ Amps and Pods are amplifiers that provide additional amplification filtering isolation and transducer support When they are connected to e corder inputs the Input Amplifier dialog for those inputs may be replaced with a dialog specific to the device This dialog 54 Chart Software Set Units for w Alland New Data C New Data Only C Selected Blocks may have extra controls for filtering offsetting and zeroing but most functions will be similar When eDAQ Amps with zeroing capability Bridge Amp GP Amp QuadStat are connected the command Zero All Inputs in the Setup menu is enabled It allows you to simultaneously zero the signals from multiple eDAQ Amp channels instead of having to zero them individually through their respective dialogs For more details on controlling eDAQ Amps and Pods from within Chart please consult their manuals Units Conversion Units conversion lets you convert the standard voltage reading for a channel into suitable units for display You can calibrate the channel using waveform measurements or known relationships The conversion can be applied before recording so that all subsequent recordings are scaled to the required units or after recording either to the entire channel and all subsequent recordings or to particular blocks of data Each channel is set up independently To open the Units Conversion
152. e file list as shown in Figure 5 1 containing comments about the contents of the selected folders 96 Chart Software Figure 5 1 The Experiments Gallery dialog V Refer Experiments Gallery Configuration Files p20 Figure 5 2 Creating the Experiments Gallery folder Experiments Gallery Experiments Gallery Files for Vibration experiment E Chemistry Experiments Physics Experiments H TLO Ohms Law S TL02 vibration TLO b Reade td Read this first it explains what s in this experiment module TLO2b Vibration edcht ae Example data file Hees TLO b Settings File edcht us This fle contains the settings needed to record your own data TLO b Vibration pdf This iz a POF of the procedure for this experiment ou need Adobe Acrobat Reader to read it Show Experiments Gallery at startup Open Individual files may also have labels describing them in addition to their file name An Errors button may appear at the bottom of the dialog if there are any problems with files or folders in the Experiments Gallery for example a file referenced in a configuration file is not present in the Experiments Gallery folder Clicking on the button displays a message with further information Managing the Experiments Gallery If you are a teacher or a researcher you will probably want to create an Experiments Gallery tailored to your own needs First create a folder called Experiments Gallery in t
153. e first or second derivative of the waveform in the source channel The first derivative is the slope the second derivative is the rate of change of slope The units of the differentiated waveform are based on those of the source channel For example if the source has units V volts then Pressure Chart View Idle Le 1 ooe os e ee Bie fo ees ee ao pas oe ee oe Z 0 00e 00 Ps PAE a k PALATE PE T AA A e E E E 2 00e 05 im JE E E Suni a ae E E x Pa T im I E E Chapter 6 Data Analysis 171 WV Refer The Derivative Calculation p 241 the units will be V s for a first derivative or V s s for a second derivative Details of the algorithms used to calculate the derivatives are given in Appendix C Scaling By default the Auto scale checkbox is selected which causes Derivative to estimate the most appropriate scale for the channel when there is data to base a scale on If channel data is unusual and the checkbox is deselected a scale can be assigned manually You can type in directly the extent of the scale to be displayed in the Set scale text entry box This deselects the Auto scale checkbox This option allows you to adjust the Amplitude axis directly to display a desired range of values just as you can with the Set Scale dialog available from the Chart View The scale will affect the accuracy in signiticant figures of the displayed numbers Note though th
154. e name here e My Network Save as type Chart Data File adicht j selections of Chart data directly into a Chart document for this probably a quicker option in most cases but less able to be easily automated via macros for instance If you split the data display area of the Chart View vertically into two sections or panes you can save selections from the left hand pane during sampling at slower rates This lets you deal with recently recorded data in a separate document while still recording Appending Files Choose Append from the File menu to append a file to an open data tile The File Append dialog will appear Select the file to append to the currently open file and click the Open button to append it The Files of type drop down list lets you choose the sort of file to open only the chosen type appears in the scrolling list Chart data and settings files are usually the only choices Note that appending works differently for the two file types Appending a Chart data file to the end of an open file produces a single file containing the data of the open file followed by the data of the appended file By combining this feature with Chart s ability to save selections of data as files summary files can be created using only those segments of recordings that have significance All comments will be copied across and renumbered following on after the last comment in the original file Settings from the appended
155. e on the left side of each channel s Amplitude axis Click the button to enlarge or the button to reduce the vertical scale halving or doubling what is shown each time Holding down the Ctrl key while using the Scaling buttons keeps the bottom end of the scale fixed while halving or doubling what is shown Holding down the Alt key while using the Scaling buttons keeps the top end of the scale fixed while halving or doubling what is shown Dragscales The pointer changes as it is moved over the Amplitude axis area At the left of the area it is a normal leftward pointing arrow To the right of the area though the pointer points to the right and a small marker appears beside it indicating its function Between numbers on the scale a double headed arrow appears beside the cursor Dragging up and down will shift the whole scale Holding down the Shift key causes the double headed arrow to be displayed at all times wherever the cursor is on the scale If the pointer is opposite a number on the scale and above the midpoint of the axis two upward pointing triangles appear beside the cursor Dragging upward will stretch the scale and dragging down will compress it keeping the bottom end of the scale fixed in either case Holding down the Ctrl key causes the upward pointing triangles to be displayed at all times wherever the cursor is on the scale If the pointer is opposite a number on the scale and below the midpoint of the axis
156. e this document Save with new name location format Save the selected data to a file Set up page attributes for printing Preview printing from active window Ctrl P Print the active window List of most recently used files Use Functions2 edcht Alt list number as keyboard shoutcut 3 CAProgram Files 4D0Instrument Waveforms adicht 4 CProgram Files 4DInstr Srioothing Cemo adicht Exit Alt F4 Exit Chart Undo Sampling Chril 2 Cut Chart Data Chris Copy Chart Data 9 Chrl Paste Ctrl V Paste at End Cbrl ShiFk Clear Selection Delete Select All Ctrl 4 Clear Channel Default Settings Preferences License Manager Undo previous operation Redo the previously undone operation Cut the selection and place it on the Clipboard Copy the selection and place it on the Clipboard Paste the Clipboard contents at the insertion point Paste the Clipboard contents to the end of the file Delete the selected data Select all the data in the file Delete all data and comments from the selected channel Specify the settings of new Chart documents Customize Chart options see submenu Open the License Manager dialog Figure A 4 e corder Startup Set startup mode for Chart and e corder detection The Preferences Data Buffering Change how and to which disk data is buffered submenu Menus Hide or lock menus and menu items i e corder fs Controls Allow or disallow printing of whole document Cursor
157. emove a slowly changing signal component when recording a fast signal superimposed on a slowly dritting baseline for instance Low pass filtering The Low pass drop down menu gives a choice of low pass filters from 2 kHz down to 1 Hz to remove high frequency components such as noise from an input signal To turn them off altogether the default setting choose Off from the menu These are not anti aliasing filters Other filters can be applied after data collection with the Digital Filter channel calculation Note that digital filtering calculations are done in the e corder and use some processor power so if you are using the digital filters on many inputs you may not be able to use the fastest sampling rates or you might have to turn off one or more inputs in order to sample Mains filter By selecting the Mains filter checkbox you can filter out interference at the mains frequency typically 50 or 60 Hz Note that in general it is better to prevent interference at its source than to filter it The mains filter is an adaptive filter which tracks the input signal over approximately 1 second It analyzes the signal in such a way as to create a template of any interference due to the mains frequency see Appendix C Subtraction of the template from the incoming signal cancels most of the interference In comparison with a conventional notch filter this method produces little waveform distortion It attenuates harmonics of the main
158. entheses 254 Chart Software FIND search_text text start_position Searches for a string of text within another text string and returns the character position at which the search string first occurs FLOOR number significance Rounds a number down to the nearest multiple of a specitied significance HLOOKUP search_item search_range row_index Searches the top row of a table for a value and returns the contents of a cell in that table that corresponds to the location of the search value HOUR serial_number Returns the hour component of the specified time in 24 hour format IF condition true_value false_value Tests the condition and returns the specitied value INDEX reference row column range_number Returns the contents of a cell from a specified range INDIRECT ref_text a1 Returns the contents of the cell referenced by the specified cell INT number Rounds the supplied number down to the nearest integer ISBLANK reference Determines if the specified cell is blank ISERR expression Determines if the specified expression returns an error value If the expression returns any error except N A True is returned Otherwise False is returned ISERROR expression Determines if the specified expression returns an error value If the expression returns any error value such as N AI VALUE REF DIV O NUMI NAME or NULL True is returned Otherwise False is returned
159. erage slope time derivative of the data points in a selection or the slope at an active point The average slope is calculated from the leastsquares line of best fit This fits to the number of points in the selection except for an active point or single point selection both of which fit to three points Maximum Slope returns the maximum slope of the data points in a selection or the slope at an active point Time at Maximum Slope returns the time at which the maximum slope in a selection occurs or the time at an active point Minimum Slope returns the minimum slope of the data points in a selection or the slope at an active point Time at Minimum Slope returns the time at which the minimum slope in a selection occurs or the time at an active point Integral Integral returns the integral of the selection calculated as the sum of the data points multiplied by the sample interval gt y At Integral from Minimum returns the integral of the selection calculated as the sum of the data points minus the lowest value in the selection multiplied by the 142 Chart Software Vv Refer Cyclic Measurements p 165 sample interval Y Y min At Integral from Start returns the integral of the selection calculated as the sum of the data points minus the first value in the selection multiplied by the sample interval gt y y 4 At Integral from Baseline returns the integral of the selection calculated as the sum of the da
160. ere are three menu commands in the File menu to do with printing Page Setup Print Preview and the basic Print command with a keyboard shortcut of Ctrl P which changes depending on what can be printed at the time Page Setup Choose Page Setup from the File menu to open the Page Setup dialog Choose the paper size tray orientation and margins that you will be using You can look at printer specific features by clicking the Printer button The user s guide that came with your printer should explain these features Page Setup This picture simply shows the page orientation portrait or Paper Size Letter 8 5 x 11 s Source Auto Tray Select w Orientation Margins millimeters Portrait Left Bight 12 7 Landscape Top l Eottom Print Preview If a Chart View is active you can choose the Print Preview command in the File menu to open the Print Preview dialog This is a fairly standard dialog for Windows applications and shows what the file will look like as printed pages You can use the arrows at the top left of the 118 Chart Software Figure 5 18 The Print Preview dialog dialog to move through the document s pages and the buttons beside them to view one or two pages at a time Note that you can change a document s horizontal compression to fit more or less on a page 28 Chart Print Preview foo Page 1 2 TL lac O20 Fle Jur ont JALIL ALE ALEN LLL
161. erivative order is O in which case the fit order is set to 1 and the window width is set to be greater than the fit order The four integral functions Integrate IntegrateAbs IntegratePos and IntegrateNeg are equivalent to the four integral types available in the Integral channel calculation dialog Figure 6 27 A source channel is required as a parameter a number of other optional parameters can be specified depending on the resetting mode chosen The default values of these optional parameters are the same as in the Integral channel calculation except that if you use the Timed Reset or Time Constant Decay resetting mode in Arithmetic the default time is one second Shift is equivalent to the Shift channel calculation and requires a channel as a parameter The time shift parameter is optional as with the Shift channel calculation the default is zero seconds Chapter 6 Data Analysis 163 Smooth is the same as the Smoothing channel calculation except that it always uses a triangular Bartlett window The Smooth function requires a channel as a parameter The window width parameter is optional as with the Smoothing channel calculation the default is three points The six filtering functions Lowpass Highpass Notch NarrowBandpass Bandpass and Bandstop are the same as the corresponding filters in the Digital Filter channel calculation except that Bandpass and Bandstop allow you specify a diffe
162. ers shared M it b tt display a second E P C Smoothing Minimum peak height 5000 mis Cycle markers trace and the Settings to ri hth an d V Differentiate trigger on slope max or min C Minimum period Trigger Maximum g one detect and Amplitude oxis mark cycles 166 Chart Software V Refer The Amplitude Axis Dry a second Amplitude axis at the right of the signal display area You can chose whether cycle detection triggers on the maximum or the minimum of the derivative using the Trigger drop down list at the lower right of the dialog Detection Parameters Detection parameters relate to the waveform displayed in the signal display area If any preprocessing smoothing or differentiation is applied then cycle detection is relative to the black preprocessed waveform and you may need to refer to the right hand Amplitude axis for peak heights The Minimum peak height you enter is the height the waveform must rise after the previous peak and then subsequently fall for the current position to be taken as a peak It should not be considered as a threshold for cycle detection Setting a Minimum period prevents two peaks from both being recognized within that time period the second peak will be ignored Cycle markers are always shown for detected peaks in the signal display area but are only shown in the Chart View if the Cycle markers checkbox is selected The Trigger drop down li
163. es the dependent data in all other views The sharing of detection settings by two or more channels or Data Pad columns is indicated in the Cyclic Measurements dialog as shown in Figure 6 19 Derivative Derivative calculates the first or second time derivative of the data in a channel It works online during recording as well as offline Choosing the Derivative command from a Channel Function pop up menu displays the Derivative dialog for that channel As with most channel calculations you specify a source channel in the Source channel drop down list 170 Chart Software Figure 6 21 The Derivative dialog with default settings Figure 6 22 Pressure signal top trace with first and second derivatives calculated by the Derivative channel calculation Derivative Channel 1 Source channel v Window width paints Derivative order isk w Set scale 100 Units is e Decimal places Auta scale The Window width control lets you set the number of points used to calculate the derivative The width is always an odd number the smoothed point and a variable number of points on either side Click the up or down arrows to increment or decrement the number or type in the number of points from 3 to 255 in the text entry box You may need to experiment with the window width to get a result which is not overly affected by bias or noise The Derivative order drop down list specifies calculation of either th
164. ettings are blank and unusable Channel Title You can enter a title of up to 21 characters for each channel in its text entry box replacing default titles such as Channel 1 Range The drop down lists in the Range column let you select the input range or sensitivity of each input Changing the range is equivalent to changing it in the Chart View Input Settings Click the Input Settings column to access the Input Amplifier dialog for an input letting you change input settings apply signal filtering etc and see the effects without recording This is the same as choosing the Input Amplifier command from a Channel Function pop up menu By default Chart channels display data recorded from their corresponding 60 Chart Software V Refer The Input Amplifier p 50 V Refer Units Conversion p 55 V Refer Computed Input p 184 E V Refer Display Settings p 82 Eg Calculation No Calculation e corder inputs The column entry will change to show if an eDAQ Amp such as a Bridge Amp is connected So this column can be used to check if multiple eDAQ Amps are connected properly to the e corder and are on Units Click the Units column to access the Units Conversion dialog for a channel letting you change the standard voltage reading for a channel into useful units such as mmHg and kPa This is similar to choosing units conversion through the Input Amplifier dialog and applies only to subseque
165. f 200 000 s e These are the system limits for e corders and can t be changed Turn off the external trigger when sampling at 200 000 s reduce the number of channels used at fast rates etc Faster computers allow faster sampling rates on more channels e Ensure that the e corder computer and connection are appropriate to the sampling rates you want e Turn off unused channels and digital filters The extra work can limit Chart sampling rates e Channels do not need to be visible to record data so check that any bunched up in the Chart View are actually off Background activities other applications etc will decrease the ability of the computer to cope with the data from the e corder e Turn off anything other than Chart that could slow down or interrupt data sampling e Ensure that your disk is not too full and is not fragmented either slows down the speed of writing to disk You can change the disk to which data is buffered and how often data is buffered to that disk to increase performance Nothing seems to be recording e The Record Monitor button bottom right of the Chart View by the Start button may be set to Monitor there will be a cross through it if this is Appendix A Troubleshooting 233 V Refer Data Buffering p 41 so and the Chart View Title bar will read Monitoring data after the document title and incoming channels will be grayed e Click the Record Monitor button t
166. f Figure 6 41 if the amplitude were much smaller the triggering would be lost Cyclic Maximum Minimum and Height In the Cyclic Maximum function the trigger threshold identifies cycles At the end of a cycle the maximum data point found within that cycle is shown until another cycle has been measured The Cyclic Minimum function works similarly except that the minimum value of a cycle is found and displayed during the next cycle The Cyclic Height function determines the maximum minus the minimum value These functions are useful for showing the cycle by cycle minima or maxima for quantities or the difference between the two Chapter 6 Data Analysis 193 Figure 6 42 Cyclic maximum the largest value attained by the waveform in the previous cycle is displayed Maximum from previous cycle period Abs and RMS Smoothed Abs Smoothed smooths using the absolute values of the preceding data points over the time set in the Smooth pop up menu RMS Smoothed root mean square smooths using the square root of the average of the squared amplitudes of the preceding data points over the time set in the Smooth pop up menu In each case the data points are sampled at 2000 samples per second or faster These two functions effectively provide a form of modified moving average and are useful in acoustic and vibration studies Envelope Maximum and Minimum Envelope Maximum finds the maximum value of the data points over
167. f Trigger is selected recording starts at the trigger event and continues for the set period after the end of the trigger event when the voltage passes through the trigger level again If multiple trigger events occur during recording recording continues until the set period after the end of the last one provided that the set period is longer than the time from the end of one trigger event to the start of the next You might use this to record while a nerve was firing for example and for some time afterwards recording would start when the nerve potential starts and stop a set time after the nerve potential falls below a certain value The Stop time controls are used to set the time period for which recording continues and are only active when either Fixed Duration or End of Trigger is selected in the Stop drop down list Click the up and down arrows to increment or decrement the numbers or type a value in the text boxes directly If you are recording for a long time at a high sampling rate check to see if there is enough memory to record for the time entered to do this see Duration of Recording p 40 66 Chart Software Figure 3 12 The External trigger marker drop down list V Refer The Stimulator Panel p72 When either Fixed Duration or End of Trigger is selected in the Stop drop down list you can specify the number of blocks you wish Chart to record by checking the Stop cycling after checkbox and setting t
168. fference between the largest and the smallest data points in the selection RMS calculates the RMS root mean square value of the data points in the selection or returns the value at the active point 1 3Max 2 3Min calculates 1 3 of the maximum value plus 2 3 of the minimum value of the data points in a selection or returns the value at an active point Chapter 6 Data Analysis 141 Selection amp Active Point Time returns the start time of a selection or the time at the active point Date returns the start date of a selection or the date at the active point Value returns the value at the start of a selection or at the active point Selection Start returns the start time of a selection or the time at the active point Selection End returns the end time of a selection or the time at the active point Selection Duration returns the duration of a selection zero for an active point Number of Points returns the number of data points in the selection zero for an active point Comments Comment Time returns the time at a commented point Comment Number returns the number of a comment Extract Numbers in Comment Text extracts the first number from comment text e g Add 100 mL of 2 mM would return 100 Full Comment Text extracts the full comment text In each case the Data Pad looks for the first comment to the left of an active point or from the right edge of a selection Slope Average Slope returns the av
169. file page 116 to produce recording summaries conveniently in a single file You can even copy cut and paste data directly within a Chart file page 103 or between files Data can be transferred as text to other applications such as spreadsheets or statistics programs page 104 Analysis When you have finished recording you can scroll through your data and make measurements directly from the recording page 130 you are given a direct read out with no chance of measurement errors You can measure relative to a set reference point using the Marker page 130 You can search channels for comments peaks and troughs in the waveform block boundaries etc and select data according to criteria you specify page 132 The Data Pad page 135 calculates and stores statistics about recorded data and can be printed out or have its data transferred to other applications You can plot data from one or two channels against another either online or offline using the XY View page 147 In the Zoom View page 88 you can examine a section of the recording in more detail overlaying channels for direct comparison if you wish The Spectrum window page 151 allows flexible analysis of the frequency components of your waveform Advanced Features Triggering functions page 63 let you control when Chart starts and stops recording using internal or external measurements The Stimulator page 67 allows you to set up a voltage output signal for an ex
170. for all number box you type add the comment Chapter 2 Introduction to Chart ar Figure 2 15 General and channel specific comments and the pop up comment box Comments are stored and saved along with recorded data Comments are marked by a dashed vertical line text and comment box inserted in the appropriate channel on the record or across all channels if the comment applies to all channels When you have finished recording you can read the time and the full text text of long comments may be truncated in the Chart View of each comment by placing the pointer over the comment box and clicking a box pops up displaying the comment Comments can also be added after recording by choosing Add Comment from the Commands menu and can be read edited deleted found and printed from the Comments window Comment boxes lines and text can be hidden if this is desired fiz mY ri esununnennnenupuunnnunnnnununuunnnnununnununununnusunnununnnunnnsunnununnnunnnsunnununnnunnnnunnunnnnnnn a oo pi N ali The pop up comment box also shows the Background Recording Recording is not an all or nothing process you can do other things while recording in Chart You can review recorded data compare old data with new by using the split screen feature or leave Chart recording in the background even when the window is minimized while you run other applications This is useful for longer recordings since
171. formation to the Data Pad copying or printing the selection or saving the selection as a file these operations will use the full array of data points over the recording period of the selection Altdrag to select the full height of a channel To add channels to a selection hold down the Shift key and drag in the display area of the channels you want the vertical extent of the selected rectangle in other channels can be varied but the horizontal extent will be the same as that in the first selected channel The recording period over which selections are made in multiple channels must always be the same AltShift click in the display area of a channel you want to add to select its full height 2 ET 2 Time axis pointer To select an area of data in all channels position the pointer in the Time axis area the pointer will change to a double headed arrow Drag in the Time axis area to highlight a rectangular area over all channels Shift click along the Time axis to extend or contract the selection from its nearest edge to the point at which you click Shift click in the display area of a selected channel to deselect it Double clicking in the Time axis selects an entire block of recorded data the whole file if it is continuous Choose Select All from the Edit menu or type Ctrl A to select the whole file When there is a selection in the data display area some of the menu commands available change to reflect this In the File menu
172. g or after recording by choosing Add Comment from the Commands menu or by typing Ctrl K which displays the Add Comment dialog Type in the comment and click the Add button or press the Enter key to add it to the file Comments are numbered in the order in which they are added and not necessarily left to right across a file Add Comment Yew Comment Insert at selection Channel drop down list Insert at end of data The radio buttons and channel drop down list reflect the state of Chart when the dialog is displayed e the Insert at selection radio button is selected if there is a selection or active point in the Chart View and Chart is not recording o the Insert at end of data radio button is selected if Chart is recording or there is no selection or active point in the Chart View e the channel drop down list displays the title of the channel that contains the selection or All if the selection in the Chart View involves more than one channel Chapter 5 Working With Files 123 Figure 5 24 General and channel specitic comments and the pop up comment box Depending on which radio button is selected the comment is either added at the active point or at the midpoint of a selection or at the end of the file You can choose between the two even when recording but if Insert at selection is selected and there is no selection or active point no comment is added when the Add button is clicked You can use the c
173. g several units Any of these units can be chosen from the Threshold Unit drop down list Chart will display integrals for blocks of source data if corresponding blocks of data in the Event channel use the units chosen in the Threshold Unit drop down list If a block of data in the Event channel uses a unit other than that chosen in the Threshold Unit drop down list no integral will be shown for the corresponding source data that block will appear empty Integral Limits When the Integral limits checkbox is selected all integrals are calculated as definite integrals over the indicated limits At times less than the first limit the integral is zero At times later than the second limit the integral holds its value constant This mode is most likely to be useful in a recording with multiple data blocks For example in a series of electrical responses to nerve stimulation you may wish to set the first limit just later than the stimulus time so that the stimulus artefact does not contribute to the integrated response If you accidentally select the checkbox with the default limits of O and O all integrals will be zero Scaling By default the Auto scale checkbox is selected which causes Integral to estimate the most appropriate scale for the channel when there is data to base a scale on If channel data is unusual and the checkbox is deselected a scale can be assigned manually You can type in directly the lower and upper limits of
174. g the Save As button accesses the Save As directory dialog which allows you the complete range of options in saving a Chart file It is useful where you have disabled the ability to save a file and particularly to save the file as a Settings file with the hidden or locked menu items remaining as specified when the file was saved Clicking the Data Buffering button accesses the Disk Buffering dialog letting you choose where data will be stored while recording and how disk buffering is done This is useful if you have accidentally disabled the Data Buffering menu command Macros Macros are used to group sets of commands together conveniently enabling you to speed up repetitive and tedious tasks such as changing the settings for various parts of an experiment They can help to automate recording and analysis They record the results of your actions step by step then reproduce them when played back If you tind yourself regularly doing the same series of operations in Chart whether simple or complex macros can ease things considerably Macros can record almost any Chart operation setting dialog and 206 Chart Software window controls changing the display format copying waveform data to the Data Pad saving data as a new file printing the Zoom View display of selected data etc There are some differences between recorded and real operations but in general dialogs will guide you through the options It is important t
175. gh to allow at least 5 to 20 samples for any transient peaks or recurring waves in the signal The highest frequencies in a signal can be formally determined by sampling the signal at the maximum rate and looking at the spectrum of the signal using the Spectrum window High frequency components in the spectrum with less than 2 or so of maximum amplitude usually contribute little to recording accuracy Filtering Any analog waveform can be described mathematically as the sum of a number of pure sine waves at various frequencies and amplitudes Low frequencies characterize the slowly changing parts of a waveform high frequencies the quickly changing parts A filter removes selected frequencies from a signal for instance a low pass filter lets low frequencies pass and stops high frequencies Low pass filters are commonly used to help reduce noise and give a smoother signal A Chapter 1 Getting Started l5 Figure 1 7 The effects of filtering on a mixed frequency signal a high pass filter removes low frequencies a low pass filter removes high frequencies high pass filter removes any steady component of a signal it also removes slow fluctuations Filters are imperfect A 200 Hz low pass analog filter say might leave frequencies up to 150 Hz untouched reduce a 200 Hz signal to 0 7 of its original amplitude this is its cut off frequency and reduce higher frequencies more and more If you were expecting useful freq
176. h channel from the list of channel titles Two scrolling lists let you select from the many forms of information that could be sought The left hand list gives the general type and the right hand one options available in that set The selected option is briefly explained in a box beneath the two lists The exact controls in the dialog depend on what is chosen in the scrolling lists Go Go can find the start or end of the file or the current block within the file the start of the next block or the end of the previous block You can also move forward or backward through a file by a set time in seconds If you select the Move forward or Move backward options a text entry box appears in which you can type any number This always moves at least one data point whatever the sampling rate Find Data Find Data can search for local maxima or minima or data points above or below a set value The search direction is set by the direction arrows to the right of the Channel drop down list Click the right arrow to search forward the left arrow to search backward If you select the Local maxima or Local minima options Find Data searches for peaks or troughs respectively A text entry box appears in which you can type in a number from just over O to 90 to set a noise threshold for the event as a percentage of the range of the channel the default value is 5 which is 1 V for a 10 V range For a data point to be recognized as a peak or trough t
177. hannel drop down list to change the channel the comment will apply to or to apply the comment to all channels A comment can be pasted into the text entry box While a lot of text can be entered more than 60 characters or so will not be clearly visible in the pop up comment box Reviewing Comments Once a recording has been made you can read the full text of the comments in it by positioning the pointer over the comment boxes and pressing the mouse button Figure 5 24 The pop up comment box shows the number and text of the comment as well as the time at which it is located along the Time axis in the form set by display settings To look at several comments at once locate a comment in a large file and delete or edit comments you should use the Comments window Bi cE cg ec eb ba cb Soo Bho Be oo i ce ec EELT pf CI t 247s iel e i The pop up comment box also shows the 9 00 saa time whose 1 4 3 4 5 E fn Start woo gt Eg a 10 1 ak The Comments Window To open the Comments window choose Comments from the Window menu or type Ctrl L The comments are listed down the window in the order that they appear left to right across a file and so not necessarily in numerical order The comment numbers appear in boxes as they do in the Chart View with the box preceded by the number of the channel it applies to or an asterisk if it applies to all channels Use the scroll bars to go through long lists of comments
178. hart View can be maximized thus combining with the Chart Application window to act as one window by clicking its maximize button or double clicking its Title bar It is then resized when the Chart Application window is resized etc Its title is shown in the Chart View Title bar in brackets after the application name lts minimize maximize and close buttons appear under those for the application window see Figure 2 8 The same applies to most of the ancillary windows such as the Data Pad the XY View and the Zoom View If you maximize one window in Chart then all windows are maximized Dialogs with an OK button or equivalent and miniwindows such as the Stimulator panel can be moved outside the Chart application 92 Chart Software Figure 4 13 Cascaded windows in Chart File Edit Setup Commands Macro Window Help sua e E M wm gt Start Waveforms Data Pad f fox IN Toad Heart Chart View Idle Sel Waveforms Chart View Idle Seg Waveforms Zoom View Sel E Rabbit Cardiorespiratory Chart View Idle Er _y 200 fs CO pa sy 200 m ri Fo o 20m E gt Start 944 1 MB window They are not affected by most window organization commands in the Windows menu The lowest grouping in the Windows menu see Figure A 10 lists all open windows in Chart numerically in the order they were opened Choose any window listed in the menu to bring it to the front and make it active To cycle thr
179. he number of blocks While recording the document s Title bar will show the message Recording data block x of y If the Stop cycling after checkbox is unchecked Chart will record a block of data whenever the triggering event occurs until you click the Stop button or disk space is exhausted External Trigger Marker It can be useful to mark an external trigger pulse so that you can measure response times etc To mark the point at which an external trigger pulse starts on a channel select that channel from the External trigger marker drop down list A small spike will then be marked in the selected channel overlaid on any data there If you choose Off in the drop down list no mark is recorded External trigger marker Channel 2 we Stimulation The Stimulator allows you to generate pulse or stepped waveforms using the e corder analog outputs To set up stimulation choose Stimulator from the Setup menu the Stimulator dialog will appear Figure 3 13 Its controls set the stimulus type and properties The stimulus output waveform is generated via the sockets marked Output on the front of the e corder The stimulator settings are independent of the sampling rate but stimuli can only be generated while the e corder is sampling or while the Computed Input dialog is open Parameters can be changed while sampling occurs By default the stimulator is off Off is selected in the Stimulator mode drop down list and the c
180. he Units button opens the Units Conversion dialog box letting you change the given units for the computed channel to the units of your choice The waveform in the righthand data display area is transferred to the data display area of the Units Conversion dialog box if you do this The conversion will only apply to subsequently recorded signals so it is more limited than choosing units conversion directly since you cannot convert individual blocks of data Units conversion is performed on the computed data not the raw data The Range pop up menu lets you select the range for the computed signal to get the best display This range applies only to the computed signal and is independent of the range for the raw data signal from the e corder input The Range pop up menu for a channel in the Chart View duplicates this one when the computed function is applied to the channel and the range can be changed in either place Chapter 6 Data Analysis 189 AVerage 2 H Timed Reset Reset iz z The Average control allows smoothing of the data when you want to see a trend in a Ratemeter or Period waveform rather than sample by sample changes Click the up or down arrows to increase or decrease the averaging the sequence is 1 2 4 8 with 1 being no averaging The Average control is also available for the Differential computed function with the sequence reaching 64 The control works by averaging the values of the specif
181. he data points that follow it must decrease for a local maximum or increase for a local minimum by at least the noise threshold value Local maxima and Chapter 6 Data Analysis 33 Above bo dust this channel Select all channels Set active point Select is Select to previous point minima in the waveform with smaller amplitudes than this value will be ignored Raise the threshold to get rid of unwanted small fluctuations noise etc lower it to detect missed events If you select the Data above or Data below options a text entry box appears in which you can type any number to set the value in whatever units are assigned to the search channel The first matching data point above or below the set value is found Find Comment Find Comment searches for text in comments There is only one option in the right hand list the search direction is set by the direction arrows to the right of the Channel drop down list Click the right one to search forward the left one to search backward Two more controls appear beneath the scrolling lists type text in the text entry box to find only comments containing that text ignoring case and context so new also finds New or newer Select the Just this channel checkbox to find only comments that apply to the search channel channel specific comments in other channels are excluded Clear it to find comments in any channel Selection Criteri
182. he macro while sampling but in some cases you might want to perform steps as sampling proceeds adjusting some settings for example The radio buttons in the Macro Sampling dialog allow you to 210 Chart Software Figure 7 12 The Macro Sampling dialog V Refer Comments p 122 choose between these two options The lower part of the dialog allows you to specify when sampling stops This could be useful to override for a certain portion of an experiment a fixed duration set in the Trigger dialog Macro Sampling When the macro is played back Finish sampling before doing other macro steps Bo other macro steps during slow sampling sop 0 Ab E pog Hours Minutes Seconds Preset Comments Macros let you generate predefined comments while sampling so that long comments can be entered by a user with a single keystroke using Function keys as the keyboard shortcuts To do this record a macro opening the Add Comment dialog Ensure the settings are what you want for instance the Insert at end of data radio button should most likely be on Save the macro and assign a keyboard shortcut Then rather than typing in comments in the Comments bar or Add Comment dialog while recording say you can simply use the keyboard shortcut to play the macro and add the preset comment saving both typing and time This is useful if you are doing a routine experiment or have typical things you note about recorded data Macros
183. he same folder as the Chart application Figure 5 2 Note that this folder may already exist depending on your version of Chart E Program Files Sl ebaq E charts C Demo Files Essential Files H Experiments Gallery Extensions 9 Extensions unused Chapter 5 Working With Files 97 V Refer Experiments Gallery Configuration Files p 201 Figure 5 3 An active point upper and a selection rectangle lower in a channel of the Chart View Add folders and files to the Experiments Gallery folder you have created if there are no folders or files in the Experiments Gallery folder the Experiments Gallery dialog won t appear in Chart You can organize the folders and files in a manner which suits the structure of your experiments You can add shortcuts as well as files to give access to files stored on a network for example Remember that it can be useful to add documentation text files multimedia files etc to the Gallery The folders and files will be displayed with the same hierarchy in the Experiments Gallery dialog To delete the Experiments Gallery and stop the dialog from appearing in Chart either remove all the folders and files from the Experiments Gallery folder or delete the Experiments Gallery folder entirely You can control the way the files in a folder contained in the Experiments Gallery appear by creating a configuration file and including it in the folder Detail
184. hem as a trace Derivative Channel Calculation The Derivative channel calculation provides a calculation of slope Choosing the Derivative command from a Channel Function pop up menu displays the Derivative dialog for that channel Figure C 4 Derivative Window 3 Source channel Window width paints Derivative order isk w Set scale 764063 Unitss Decimal places Suto scale The calculation is like that in the Data Pad the slope is that of a straight line fitted by least squares to an adjustable number of points Even with large values of Window width the trace calculated by the Derivative calculation remains centred with respect to the raw source signal Figure C 5 However a window width comparable with or greater than the number of samples in a peak will cause the slope to be flattened Figure C 5 lower traces Appendix A Technical Notes 247 Figure C 5 A signal and its slope obtained with the Derivative calculation The top trace is the raw signal The next five traces are the slope with window width set to 3 5 7 13 and 55 With increased smoothing there is reduction in noise flattening and broadening of the peak but no shift in time Advantages the slope is displayed as a Chart trace the slope is centred with respect to the source signal you can vary the amount of smoothing by trial and error after the recording is made Disadvantage peaks are flattened and broadened
185. hen Chart starts up it gauges the performance of the computer system at a range of tasks and works out its probable limits when sampling data Chart gives an alert if these limits are exceeded Using digital filters on multiple channels may limit sampling rates because of the time taken to do the calculations Running other applications particularly if they are CPU intensive may limit the total data transfer rate The slower the computer and the less RAM and hard disk space it has available the more noticeable this will be It is a good idea to test extended fast recording before a critical experiment using the sampling rates at which you intend to record If the computer cannot Chapter 3 Setting Up Chart 47 Figure 3 3 Channel menus Click the down arrow buttons to open the Range pop up menu left and the Channel Function pop up menu right cope with the amount of data being collected Chart will stop recording and notify you of the problem Channel Controls Each channel in the channel control area has two pop up menus Range and Channel Function Clicking on the left down arrow button opens the Range pop up menu from which you select the channel s input range The default setting is 10 volts this consistently means from 10 V to 10 V in Chart For the best resolution the amplitude of the signal you are interested in should be reasonably close to the chosen range without the risk of exceeding it If the sign
186. hich the data were recorded The sampling rates are those supported by Chart up to 200 000 samples per second Ignore non numeric lines If this checkbox is selected it is off by default Chart ignores non numeric lines in the text file including settings information data headers indicating the sampling rate etc Otherwise each non numeric line is checked to see if it is a data header starting V Refer with a recognized keyword if not an alert will appear You should Data Headers for only select this checkbox if you are importing a file that contains Reading Text p 250 irrelevant lines of text for example column headings in a spreadsheet Reading the Text Once you have chosen your options in the Open Text File dialog click OK to read in the text file Reading a text file into Chart can be slow While text is being imported into Chart a dialog indicating progress is shown To stop the process click Cancel in the dialog your Chart file will retain the data loaded into it up until the time you stop Data values can be in normal or scientific forms 3 2 34 1 2e3 for 1 2 x 10 etc A sequence of two tab characters is taken to mean that there is no data point for a reading the channel is empty at that point Time values can be in the form of decimal seconds or hours minutes and seconds such as 2 03 50 1 a m and p m are recognized as long as they are used in the format specified in your computer s time sett
187. hoose a channel here Set the Amplitude axis scale manually here Arithmetic Channel 1 Channels Scale top Turn this on to set the scale automatically smooth a waveform in one channel using the Smoothing calculation and then show the log of that smoothed waveform in another using the Arithmetic calculation Some calculations such as Arithmetic let you choose to work on the underlying recorded data of a channel as an alternative to the displayed data Arithmetic The Arithmetic calculation allows you to arithmetically combine waveform data from different channels It works online during recording as well as offline Choosing the Arithmetic command from a Channel Function pop up menu opens the Arithmetic dialog Figure 6 17 The channel from which the command is chosen and in which results will be displayed is indicated in the dialog title Choose the functions 7 below from this pop up menu Sin Math j Tosi Trig t gt l Tan Logs ag Moise F int ACost Signi ATant ae RadToD DegToRadi i Fi ee v Functions SampleTime Logiot Round0 Lrit oun E Int _ Modi Threshold Parigi windowt gaussian Differentiatet Integrater Integrals t4 gt IntegrateAabst Shift padmel Teze ifte IntegratePost Smoatht IntegrateNegt Scale bottom Unit name Filters Auto scale or Lowpass Highpasst Notch Enter units for the brat epar pes Bandpass calculated cha
188. ible or shown at the Left or Right of or Centered in the Chart data display area Setting a fixed position is useful for repeatedly finding data since you can keep looking at the same area of the screen as you go through the file Repeatedly Finding Data Once the criteria for finding and selecting an event have been set up you can choose Find Next from the Commands menu or use the Ctrl F3 shortcut to find and select the next such event You can repeat this command as needed to find multiple events it will repeat at your keyboard s auto repeat rate if you hold the key down This is easier than scrolling through manually to look for events and is very useful in conjunction with macros for instance to select successive peaks in a channel automatically and log information to the Data Pad If the Find or Find Next commands fail to find an event because the selection would move outside the file boundaries for instance then Chart should beep The Data Pad The Data Pad is used to analyze waveform data It is easy to set up and use you can record up to 255 columns of data in it either direct waveform values or calculated values from any channel from active points or over selected areas The Data Pad can store large amounts of data up to 16 380 rows of data with each cell of the 255 columns having a maximum of 255 characters Its contents can be saved as a text file or Excel file or copied in whole or part to the Clipboard fo
189. ied number of preceding samples and so may give rise to a slight phase shift in the waveform especially with the Differential function If you need to know exact times you should record the raw data separately as well The Time controls let you choose how an integral function resets to zero For periodic waves resetting corrects for cumulative errors such as those due to DC offset If No Reset is chosen in the pop up menu the Time text box is not present otherwise you can enter a value of up to 3600 seconds for Timed Reset or Time Const in increments of the sampling rate 0 1 seconds if you sample at 10 samples per second say Timed Reset resets the signal to zero after each multiple of the entered time Time Const introduces an exponential decay so that given a zero input signal the integral drops to 37 1 e of its initial value over the set time The Reset button next to the Cancel button at the bottom of the Computed Input dialog box resets the signal in the computed input data display area to zero when clicked It is only used for convenient zeroing of the display signal while in the dialog box Computed Input Functions Ratemeter Frequency or rate is how often a given event occurs within a certain time The Ratemeter function measures relatively low frequency periodic signals and gives the output in reciprocal minutes min The Ratemeter function calculates the waveform period see below and then determines the recip
190. iginal signal right unless filtered out possibility of this condition occurring you should set the range to a larger value For the best resolution the maximum amplitude of the signal you are interested in should be reasonably close to the chosen range without exceeding it That way the minimum change in voltage discernible in digitization remains small in relation to the signal being measured the signal is digitized after it is amplified If a signal is very small in relation to the range then its resolution will be degraded In extreme cases the recorded waveform may appear stepped rather than smooth Even though you could see a 380 mV signal easily enough at the default 10 V range you would use the 500 mV range to measure it at maximum resolution It would be safer in practice to use a 1 V or 2 V range though since unexpectedly large peaks could exceed the 500 mV range if the signal was not well behaved Changing the display of the waveform on screen by enlarging it in the Zoom View or by stretching or shrinking its Amplitude axis for instance does not affect its resolution just its appearance Noise Noise is defined as unwanted signal It is likely to be a problem at lower range settings when you are trying to measure very small signals Random noise such as thermal noise is inherent in all electronic circuits including those of the e corder recording unit and generally must be filtered to minimize it The
191. ill be recorded for instance If the middle radio button is selected information is recorded about the column channel only if that channel is included in the selection If the bottom radio button is selected information is recorded only about the lowestnumbered channel if more than one is selected Channel 2 if Channels 2 to 4 are selected for example C compact data The Compact Data checkbox works together with the middle radio button if you select data from different channels at different intervals after the same stimulus say it will place all the data on the same line in the Data Pad if the checkbox is deselected then each entry will be recorded on a new line It doesn t work if you record times as well so it is only useful for simple data capture Use this with care if at all rine In addition resizable miniwindows can be created to display the current values of statistics or measurements set up in particular columns from the Data Pad Click the Miniwindow checkbox in the Data Pad 140 Chart Software Figure 6 8 A Data Pad miniwindow Column Setup dialog to show or hide the miniwindow for a column or drag the column heading to tear it off Just like a DVM miniwindow a Data Pad miniwindow floats in front of the active window can be moved around by dragging its Title bar even outside the bounds of the Chart application window and can only be dismissed by clicking its close box It can be resized by dragging its b
192. imal places Set units For All and new data O Mew data only Selected blocks x Ca Caer Cie Applied Amplitude Arrows indicate the maximum mean What is units axis and minimum values in the selection converted Converting Quantities The dialog has four text entry boxes actual voltages go in the left boxes and what those readings are equivalent to goes in the right boxes Each box requires an entry so that there are two sets of values to calculate the scaling between volts and the new unit It must be a linear relationship to work Note that if the slope is negative the Amplitude axis will be inverted You can type in some or all values in the boxes directly or use some readings from the data display area in the left boxes and type in known conversion values in the right boxes Click Apply to see what the converted data look like Click OK to convert the data into the chosen units or Cancel to close the dialog without making changes 56 Chart Software AS AM Figure 3 8 Selections in the data display area of the Units Conversion dialog Entering Values If you know the relationship between what is measured and the displayed voltage then you can directly type in values in the four boxes you can press Tab to move between the fields left to right top to bottom For example if you are using a temperature transducer and calibration shows that a temperature of 10 C gives a reading of
193. in bounds Reset type options are e No Reset The integral is not reset Timed Reset Reset to zero occurs regularly at an interval entered in a text box e Reset Each Cycle The integral is reset each time the source signal passes through zero to a positive value e Time Constant Decay The integral is not reset sharply but tends to decline towards zero with a time constant as set in the text box With no input to the integral its value decays to about 37 1 e in each time constant This is like a leaky analog integrator e Reset By Event is a generalization of Reset Each Cycle The resetting event can be on any channel or threshold level on a rising or falling signal You can also set a Skip time that locks out the event detection for a specified time after an event occurs The Skip time is useful for The level at which a Channel in which the reset event is sought Source channel resetting event will occur means the same channel as the integral source data Event Options Event channel l l The logic detection Threshold j of the slope Skip seconds after event Choose the threshold unit here Further reset events ignored until this time 178 Chart Software preventing premature resetting by certain multi peaked repetitive waveforms To set these options click the Event Options button which displays the Event Options dialog Figure 6 28 An Event channel may contain data that were recorded usin
194. ing recorded In some disciplines you data acquisition usingan may be able to find tables of suggested sampling rates ranges and e corder system filter settings but these should not be applied blindly You still need to Transduce e corder hardware Computer o 101101 Mechanica Analog electrical Digital signal L signal signal Input Ampliticatio Filtering Sampling Display Pa a Chapter 1 Getting Started 13 know the science what you are recording why you are recording it and what relation it bears to real phenomena and the technique how best to record and what limitations or compromises are inherent in the process Sampling Rate Sampling replaces the original continuous analog signal by a series of discrete values samples taken at regular time intervals The appropriate sampling rate depends on the signal to be measured If the sampling rate is too low information is irreversibly lost and the original signal will not be represented correctly If it is too high there is no loss of information but the excess data increases processing time and results in unnecessarily large disk files 20 Js Figure 1 5 3 E Undersampling F120 recording a pressure signal at 20 s and 1o 200 s showing that slow sampling can fail to 25 depict the signal 200 s accurately es Recordings of periodic waveforms that have been sampled too slowly may be misleading as well as inaccu
195. ings in the Windows control panel Blocks are created in the resultant Chart data when the sampling rate changes when a new set of data headers is encountered or when a channel becomes empty as would occur if an input were turned off while recording A change in the time interval must be more than 10 of the interval to be taken as the start of a new block this allows for rounding errors For each block that is read in Chart examines the first 16 OOO values or the whole block if it contains fewer than 16 000 values and computes maximum and minimum values in each channel The upper and lower limits of the Amplitude axis scales for each channel are then set to these maximum and minimum values The default unit is volts V Chapter 5 Working With Files 111 Figure 5 11 The dialog for a non standard sampling rate This automatic scaling and the default units may be overridden by data header lines see Data Headers for Reading Text p 250 Problems Reading Text If problems are encountered Chart displays a dialog and gives you the option to stop loading data There are two common problems a strange sampling rate and invalid data Chart only supports certain sampling rates see Figure 5 10 If the sampling rate is not standard then a dialog appears and asks you to choose a standard rate from its drop down list Figure 5 1 1 Select Glock Sampling Rate 4 block of data with an unsupported sampling r
196. ional settings Saving a Selection You can choose to save a selected area of data instead of the whole tile allowing you to extract only the part of the recording that you need and place it into a new file All channels are included even if some are not selected only the horizontal extent of the selection is important If you have an area of data selected in the Chart View then the Save Selection command in the File menu is available otherwise it is dimmed and cannot be chosen If you choose the command the Save Selection dialog appears This dialog is similar to the Save As dialog except that you have a choice of only three file formats from the Save as type drop down list data file text file and Spectrum text file Once you have typed in a name for the file and selected a file format from the Save as type drop down list in the lower portion of the directory dialog you can save the selected data as a file by clicking the Save button In conjunction with the Append feature you could use the ability to save a selection for quick creation of new files containing summarized results from much larger recordings You can also paste copied Chapter 5 Working With Files 115 Figure 5 15 The Save Selection dialog Save Selection Save in Demo Files E Functions E 4 E Functions2 My Recent Mechanical Vibrations Documents My Documents 43 My Computer File name ype a fil
197. it and the buffer file is emptied ready for the next A2 Chart Software Figure 2 19 The warning that is displayed when you attempt to select Standby mode for the computer recording session When you exit Chart normally the buffer file is erased Chart for Windows Chart must be closed before the computer can be placed in standby mode amp Standby is not available whilst Chart is connected to an e corder Standby Mode When the computer is in standby mode communication with the e corder can be disrupted Chart prevents you from selecting standby mode Start gt Shut Down for the computer whenever Chart is connected to an e corder and overrides any standby settings made in Control Panel gt Power Options This prevents you from inadvertently putting your data recording at risk and the operating system from interrupting a recording when no other activity has occurred for a while Chapter 2 Introduction to Chart 43 44 Chart Software CHAPTER THREE Setting Up Chart Chart gives easy access to basic settings and also offers a flexible array of setups suitable for different types of data This chapter describes basic controls for the sampling rate and the input range together with features such as input amplification units conversion triggering stimulation and sampling using multiple e corders Chart Software 45 Figure 3 1 The Rate pop up menu an
198. l calculations are applied Checking the Expression Syntax When you click OK Arithmetic checks to see if it can understand the expression If it cannot an error message will be displayed Possible causes of problems are missing brackets or having nothing at all entered Also note that most functions that includes brackets such as Abs require an argument that is something to operate on within the brackets The exceptions are Random and Gaussian where an argument is optional If you enter a function without an argument the error message indicates the correct usage of the function which can be useful if you are unsure what parameters are required as arguments Calculation Errors A numeric error can occur in various circumstances such as division by zero the square root of a negative number or the logarithm of a non 160 Chart Software positive number In the event of such an error the calculated result is indicated in the Chart channel as Out of Range Internally an error result is represented as a NaN Nota Number Math Functions Basic mathematics functions add subtract multiply divide can be entered by typing using the buttons or choosing from the Math submenu of the Functions pop up menu The power 4 function can also be typed or chosen from the Math submenu It raises a number to the power of the number that follows the symbol Trigonometric Functions Trigonometric functions can
199. lar that a repeated sequence was ended in the wrong place Try recording it again 234 Chart Software Crashes Chart quits unexpectedly crashes or freezes If Chart quits unexpectedly or crashes then there may be a system problem If the behaviour is repeated then some non standard system configuration is most likely to be the cause e See your e corder Manual and the guide that came with your computer for more details on this problem and how to deal with it You may need the help of a technical support person The file you are using may have become corrupted possibly through disk damage especially if it was transferred from a floppy disk e Use disk checking software to find and fix the problem It may be that the application has become damaged in some way e Try reinstalling Chart from the original Software Installer CD It could be that a computer virus is causing the problems e Check your disk with anti virus software If you find a virus you should check all potentially affected computers disks and backups and eliminate the infection It is possible that there is a problem with the program itself e Check to see if the problem occurs again If so note down as many aspects of what you were doing as possible use the Configuration Information dialog and add any relevant details such as sampling rates and the like and notify eDAQ Appendix A Troubleshooting 235 236 Chart Software
200. lation and display of the spectrum can be set The Spectrum Settings dialog can be kept open so that changes to settings can be observed in the Spectrum window the spectrum will be recalculated or redrawn as you change settings 152 Chart Software Figure 6 13 The Spectrum Settings dialog Vv Refer Windowing Functions p 240 Spectrum Settings FFT size Data window Cosine Bell Method 50 Overlap Selection Use Current Display Power Display as Lines Remove zero Frequency component Close FFT Size The Fast Fourier Transform works on a discrete number of data points the FFT Size at a time over the selection to be analyzed The larger the FFT size the greater the frequency resolution the number of frequency bins into which the signal is resolved Smaller FFT sizes give a higher amplitude accuracy but a lower frequency resolution The FFT sizes available are various powers of 2 from 128 to 128K data points 1K 1024 points Data window Windowing functions reduce the importance of data at the edges of the data segments used by the FFT thus preventing spurious peaks arising from edge related effects There are many such functions but they are all basically similar By default Cosine Bell is chosen in the Data window drop down list but you can choose the Cosine Bell Hamming Blackman or Welch windowing functions More details on the windowing functions can be found in Appendix C page 237
201. layed on that axis Click the numbered buttons to change the assignment The x and y axis controls are the same as those of the Amplitude axis in the Chart View both axes have a Scale pop up menu and Scaling buttons and you can shift or stretch the various axes by moving the pointer over them and dragging The buttons at the top of the window control the appearance and behavior of the trace in the XY View how they work depends a little on whether you are using the XY View in online or offline mode Two different channels can be assigned to the independent left and right hand y axes In this case the signals form the two selected channels are shown overlaid versus the common x axis Figure 6 11 You can adjust the scaling of each y axis independently to stack or overlay the signals The color of each signal shown in the XY View is determined by the selection of the y axis channel in the main Chart Window If you alter the color of the signal on a channel in the main Chart Window it will also change in the XY view If you are printing the XY View window using a black and white printer then adjust the line style of the signals use the Line Style button to be different so that they are easly discenible Online Operation To view the dynamic XY plot while recording with Chart it is convenient to tile the Chart and XY Views This can be done either 148 Chart Software Selection m x os D Persistence 3 5 3 7
202. lculates the average of the cyclic minima in the selection Average Cyclic Maximum calculates the average of the cyclic maxima in the selection Average Cyclic Height calculates the average of the cyclic max to min differences maximum minus minimum in the selection Average 1 3 Max 2 3 Min calculates the average of the cyclic 1 3Max 2 3Min values in the selection 1 3Max 2 3Min calculates 1 3 of the maximum value plus 2 3 of the minimum value of the data points in a cycle Source Data for Rows Data Pad rows contain hidden information to link them back to the Chart data selection from which they were derived To link Data Pad rows to other applications see page 104 The link allows you to e reselect the source data for that row in the Chart window e recalculate the row data These options are described below Reselect To review the data source for a row select the row in the Data Pad and choose Reselect Data from the Data Pad pop up menu or double click anywhere in the row If required you can now adjust the extent of the selection for example by Shift clicking in the Time axis or by using Set Selection from the Commands menu Data about the current selection displayed in the row just below the column headings can be used to 144 Chart Software Figure 6 9 The Save as type drop down list showing options for saving the Data Pad as Text or Excel replace the values in any row by selecting the row and choo
203. le 1 3 6 You can use this format to enter the numbers of the channels you want included in the selection so typing 3 5 will include channels 1 3 4 and 5 1 Channel 1 2 channel 2 3 Channel 3 4 Channel 4 5 Channel 5 6 Channel 6 7 channel 7 amp channel amp Chapter 5 Working With Files 10 V Refer General Display p 84 Deleting Data There are two sorts of data deletion available in Chart You can clear a selected area of data for all channels or you can clear all of the data recorded in a particular channel you cannot just delete an area of data in one channel These two options are only available when the Chart View is active and you are not sampling To delete an area of data common to all channels drag along the Time axis to select the area corresponding to the period between two points on the axis then choose Clear Selection from the Edit menu or press the Delete key In fact if there is any selection in the Chart View in one or more channels these actions will clear data from all channels over the period of the selection This is useful to delete stretches of a recording where nothing particularly interesting occurred The Cut Chart Data command Edit menu does much the same thing but preserves on the Clipboard a copy of the data deleted from the Chart View which means the data can be pasted elsewhere Since you create a discontinuity in the record by deleting
204. les per second if the pointer is over the channel control area When recording the Date miniwindow shows the current date Otherwise it shows the date at which the data points tracked by the Waveform Cursor were recorded if the pointer is over the data display area or Time axis or is blank if the pointer is over the channel control area When recording the DVM channel miniwindows show the current input value in the units used for the channel if an input is off then Input Off appears Otherwise they show the current range of each channel if the pointer is over the channel control area or the amplitude of the waveforms at the position of the pointer if it is over the data display area or Time axis The miniwindows update a few times per second when recording Organizing Chart Windows As you open documents and their associated windows in Chart you can end up with a cluttered application window whose contents are difficult to find or to identify at a glance The simplest solution is not to keep open too many windows at once of course but there are other ways to deal easily with any clutter Chart offers the standard organizing commands to organize windows within the Chart Application window Chart Document windows are contained within the Chart Application window and can never escape or spill over onto the desktop Within these confines they can be moved resized closed maximized restored shrunk to a minimized state etc The C
205. log V Refer Figure 1 2 p 11 License Manager The Chart License Manager allows you to view add and delete license codes for Chart Choose Edit gt Preferences gt License Manager to open the License Manager dialog Figure 7 2 Chart License Manager NEEQ LOO 4 22 Chart 5 Single User License Existing license codes and their descriptions are shown in the lower half of the dialog Note that the last four characters of the license code are shown as xxxx you will have been provided with the full license code including the last four characters when you purchased the software To add a license code enter it into the License Code text box and click Add The new code will appear in the dialog To delete a license code select it and then click Delete You will be asked to confirm the deletion If you delete your Chart license code the next time you try to run Chart you will be prompted to enter a valid license code Chart will not run until you have done this If you delete all the license codes shown in the License Manager dialog you can edit the entries in the Name and Organization text boxes e corder Startup Normally when Chart is started it checks for e corders connected to any USB port of the computer If no e corder is found you are offered the choice of searching again or of using Chart in analysis mode without an e corder To set startup options choose Edit gt Preferences gt Hardware Unit Startup
206. lt comments apply for all channels when this is the case the numbered comment box is preceded by an asterisk To comment on a specitic channel either select the text in the Channel field and type the number of the channel or click the channel you wish to comment on in the data display area To apply a comment to all channels type in an asterisk or click in the Time axis area at the bottom of the Chart View You can also click the up and down arrows to change channel P22 Chart Software V Refer Preset Comments piZzil V Refer Display Settings p 82 Figure 5 23 The Add Comment dialog numbers Once the channel is selected click in the text entry area and type what you want to say then click the Add button or press the Enter key to add the comment You can also use macros to add predefined comments when an event you want to mark occurs while recording at the press of a Function key If you want to add a comment quickly you could also just press the Enter key and then edit the comment in the Comments window You can do this while sampling Comments are saved along with recorded data Numbered comment boxes are inserted in the appropriate channel or for comments applying to all channels in the Time axis Comments are also marked by a dashed vertical line with the comment text alongside These options may be turned off in the Display Settings dialog Adding Comments at Any Time Comments can be added durin
207. lumns to display more on screen for example or have a wide column to the right in which to add comments Position the pointer on the dividing line between column headings so that it changes into the resizing pointer drag until the column is the desired width a line appears to indicate the new position then release the mouse button Adding Data to the Data Pad Chart offers three methods for adding data to the Data Pad In each of these the data added will depend on the choices made in the Data Pad Column Setup dialog By default the columns are set to record the mean of a channel when there is an active point rather than a selection this will be the value at the marked position on the Chapter 6 Data Analysis lar Figure 6 5 The Timed Add to Data Pad dialog waveform Any column can record data from any channel though so you could have a number of variables deriving from Channel 1 for instance Add to Data Pad To add data on a selection or active point in the Chart View to the Data Pad choose Add to Data Pad from the Commands menu or type Ctrl D As a shortcut you can double click in the data display area to transfer data at a point double clicking in the Time axis selects a block though and transfers no data If a selection straddles two or more blocks with different units then the selection will be noted as having multiple units rather than any calculation being attempted Timed Add to Data Pa
208. m Chart Licenses Extensions Addresses Documents PowerLab Front ends Pods wy edad com International Australia Tel 61 2 9607 8855 Fax 61 2 9507 3544 E mail infomedag com USA Tel 1 719 576 7000 Fax 1 719 576 3971 Email infomedag com The text can be copied from the scrolling lists for pasting into a letter email or fax to your eDAQ distributor General If you have comments or suggestions you would like to make about the Chart software or other eDAQ products please feel free to write to us directly at info edaq com or through your local eDAQ distributor We value your responses and they are taken into account when future products are released Solutions to Common Problems Chart has an extensive array of dialog and alert boxes and these will probably appear in most cases where problems arise Very often they will suggest appropriate courses of action Where they do not or where the actions they suggest fail to alleviate the problem this section of the manual should prove useful Starting Up Start up errors are mostly hardware problems and are dealt with in detail in the e corder Manual but are briefly covered here 230 Chart Software Chart starts up with strange settings menus and macros You started Chart by opening a settings file or a data file with custom settings e Start up again from the application itself choosing Chart from the Programs menu of the taskbar
209. may be placed anywhere in the configuration file and are ignored when Chart reads the file Blank lines are ignored and are useful for visually separating sections Example Below is the text of a typical configuration file The corresponding appearance of the Experiments Gallery dialog when the folder containing that configuration file is selected is shown in Figure E 1 Folder text Files for Vibration experiment 202 Chart Software TLO2b ReadMe txt text Read this first it explains what s in this experiment module flags bold TLO2b Vibration edcht text Example data file TLO2b Settings File edset text This file contains the settings needed to record your own data TLO2b Vibration pdf text This is a PDF of the procedure for this experiment You need Adobe Acrobat Reader to read it Experiments Gallery Figure E 1 Appearance of the files Demo Files Files for Vibration experiment H Chemistry Experiments in a folder called TLO2 a Vibration when the o TLO Ohms Law Read this first it explains what s in this experiment module labels ini file above has been added to the EEATT IDPationede folder ae Example data file 8 LO vibration TLO b ReadMe tt Hees TLO b Settings File edcht tE This fle contains the settings needed to record your own data TLO b Vibration pdf This iz a POF of the procedure for this experiment ou need Adobe Acrobat Reader to read it C Show E
210. mber of the printed page The file s title appears at the top of each page The Marker and pointer will not be drawn When printing a file or selection channel titles and units are included at the left of the print out and the ranges of the channels are also drawn much as things appear in the Chart View Comments are included as a numbered list at the end of the data The date and time at the start of each block is shown along the top of the printout where the block is wide enough Comments Comments allow you to annotate your recording and provide a quick and accurate method of locating specific data points in a file Comments are normally used to note briefly information specific to a particular time channel or data selection more detailed information can be recorded in the Notebook window Comments can be edited in the Comments window Using the Comments Bar During recording comments can be entered as required and are automatically numbered as they appear The Comments bar at the top of the Chart View below the Title bar is usually used for this Type the comment in the text entry area Click the Add button at the right of the text entry area or press the Enter key to add the comment to the file at the time the action is taken Channel 4 a Comment added here Add Channel the comment Comment Text is inserted here as Click this button to applies to for all number box you type add a comment By defau
211. meter Period Frequency and Counter or cyclic amplitude functions Cyclic Mean Cyclic Minimum Cyclic Maximum and Cyclic Height is selected The Baseline Tracking control is available when one of these functions or the Int Reset Each Cycle function is selected 186 Chart Software Threshold control Sensitivity control Figure 6 34 Using the Sensitivity control to stop noise triggering the computed input Threshold and Sensitivity The Threshold control sets the minimum level at which the signal will trigger the computed input for a rate or cyclic function The incoming signal must cross through the threshold level in order to register an event The Sensitivity or hysteresis control allows you to adjust how sensitive the trigger is to small signal fluctuations The Threshold control is initially set to zero if the signal has a lot of noise in this region it is best to move the trigger away from zero You can drag the control up or down to change its settings a dotted line appears to indicate where it will go When the line is in the desired position release the mouse button to apply the new settings The Sensitivity control is automatically moved with the Threshold control It can itself be dragged up to adjust the sensitivity bandwidth symmetrically above and below the threshold level dotted lines appear at the upper and lower bounds When the lines are in the desired position release the mouse button
212. ms gt Accessories gt System Tools gt Character Map you may have to install the accessory if it is absent 58 Chart Software Figure 3 9 Dialogs for defining and deleting units 9 A Decimal places Oor on v Refer Channel Controls p 48 Choose Delete Unit from the Units drop down list to delete units the Delete Unit dialog appears Select the unit to be deleted from the scrolling list and click the Delete button to delete it Shift click or Ctrl click to select several at once for multiple deletion Click OK to close the dialog and apply the deletions or Cancel to ignore deletions Define Unit os 3 i Delete You can set the number of decimal places of the new units from O to a maximum of 6 by entering text in the text box or clicking the arrow buttons of the Decimal places control under the Units drop down list To see how the units conversion will be applied click the Apply button this will turn units conversion on To apply the changes to the channel and return to the Chart View click OK You can turn units conversion off or on at any stage for any block or all the data without losing the values you have entered by clicking the Off or On radio buttons under the title of the dialog Channel Settings The Channel Settings dialog lets you set up multiple channels conveniently you can both see and specify recording and display settings for each channel in the one place To open the
213. n for four seconds and then repeat the process The internal timer is not intended for uses requiring very high accuracy It should be accurate to a quarter second as a rule but since it is controlled from the computer its accuracy depends on how fast the computer is and how busy For example holding down a menu may delay the internal timer until the menu is released and at higher sampling rates making another window active may cause Chart to stop sampling 64 Chart Software If you choose a channel as the trigger source a voltage above some threshold in the signal of that channel will start Chart recording If you do not know in advance when signals of interest are going to occur then Chart can act as a monitoring device to determine when to record The input for a channel must be turned on before the channel can be chosen as a triggering event Slope and Level Slope When External Trigger or a channel is selected in the Trigger drop down F l list the slope of the triggering voltage can be set The trigger level is an Up ce absolute voltage the slope determines whether triggering occurs when the voltage goes up positive or down negative through the trigger level The active Slope button is the depressed one of the pair click the inactive button to change the slope may The Level control is used to set the trigger level voltage for a channel when one is selected in the Trigger drop down list The range of voltage
214. n list Source channel Channel 1 w Filter type Cut off Frequency Transition width Filter sharpness 0 Auto adjust depends on sampling rate Set to 20 of Cut off frequency User defined Initial online delay will be 0 384 5 Filter Types Cut off and Center Frequencies The Filter type drop down list lets you choose one of six filter types If you choose Lowpass or Highpass you specify a cut off frequency if you choose Notch or Narrow Bandpass you specify a center frequency and if you choose Bandpass or Bandstop you specify a high cut off and a low cut off frequency Lowpass lets frequencies below the specified cut off through and suppresses frequencies above it Highpass lets frequencies above the specitied cut off through and suppresses frequencies below it Notch suppresses frequencies close to the specified center frequency and lets other frequencies through Narrow Bandpass lets frequencies close to the specified center frequency through and suppresses other frequencies Bandpass lets frequencies between the specified high and low cut offs through and suppresses other frequencies Bandstop suppresses frequencies between the specified high and low cutoffs and lets other 174 Chart Software Figure 6 25 Frequency distributions of the same noise signal filtered with Digital Filter using Frequency distributions were generated using the Spectrum window noise Attenuation dB 0 50 100 15
215. n the Baseline Tracking slider setting Slow gives a little Fast gives a lot Modified data are shown in the data display a Data limit area Trigger band Slow tracking Fast tracking Figure 6 35 shows the differences at slow and fast tracking speeds when applying a sudden change to the input signal The signal is outside the trigger band hysteresis region for much longer with slow tracking selected When using the faster baseline tracking settings the shape of the signal may become distorted but because data are only being used for triggering when baseline tracking is available the distortion does not affect calculation accuracy Figure 6 36 shows the distortion of a square wave when fast tracking is selected ee et 100 L Bo 7 Data limit area The gray data limit area that can appear at the top and bottom of the data display area indicates the full scale of the e corder input at the current range setting If the gray area moves down and meets the signal the input amplifier is overloaded this is the same as having the 188 Chart Software signal go off scale in the Inout Amplifier dialog box If this occurs select a higher input range value In general the baseline tracking rate should be set as fast as is possible without decreasing the reliability of triggering Baseline tracking also has an Off setting so it can be turned off This is useful where tracking the waveform could be counterproductive say
216. n the toolbar also duplicate these functions Compression Buttons The Compression buttons allow you to compress or re expand the horizontal scaling of a file in the Chart View the steps are 1 2 5 10 up to 2000 to 1 To see more of the file on screen at once click 30 Chart Software Figure 2 8 File title Comments Waveform Pointer Rate pop up Rate Time The Chart Application bar cursor menu display window showing a maximized Chart View Waveforms Chart View Idle IEA Range pn ee Amplitude Pads 4 07 1987 1 535 s a J J na 0 4400 t Data display area x a cc Channel i j information 0 Amplitude axis DA Range pop up Channel separator i ou sia w 1 4525 0 Channel Scale pop up menu E channel 2 x Function pop up a i menu a Channel title Scaling buttons 2 Start Sto Mi 0 5 1 1 5 2 y p Marker F z rT Pan PERETI a button Split Time Scroll Scroll Review Compression Record Monitor bar axis bar button buttons button the left far mountains button to compress it To expand the file out a Li Al again click the right near mountains button The button between the two shows the scale clicking on this button drops down a list letting vo il you choose the extent of horizontal compression directly If you print a 7 horizontally compressed file or selection then it will print at the ic compression at which you see it on screen 20 1 na The Char
217. n time is independent of the window length unlike Savitzky Golay smoothing where it is proportional to window width Savitzky Golay smoothing can be considered a gentler form of smoothing It is very good at maintaining peak heights and areas and signal slopes even when only a few data points define a feature If you find that you are using a very large number for window width to get more extreme smoothing you could probably get a similar result by using ordinary smoothing and a smaller window width Choosing the Window Width In choosing the Window width there is a similar trade off to the one made using the Derivative calculation A window width that is large in comparison with the time span of changes in the signal slope will bias the calculation of the smoothed value whereas a too small width will not effectively remove noise A signal recorded with a substantial high frequency noise component is shown in Figure 6 32 Moving average smoothing with a window width of three or five points successfully removes much of the noise 182 Chart Software Figure 6 32 Noisy recording with no smoothing top and 3 5 and 19 point moving average smoothing With 19 point smoothing noise suppression is even more effective but shortlived peaks in the signal are flattened their peak amplitude is reduced and their width increased a Demo Chart View Idle Smoothed 3 pt Smoothed 5 pt ce eer o sa oe center cents
218. nal source connected via the Trigger connector on the front of the e corder When External Trigger is selected in the Trigger dialog an Options button appears Clicking this button allows you to choose between Normal mode as described above and Contact Closure mode which means Chart starts recording when contact is made between the two terminals of the input cable The external trigger cannot be used at a sampling rate of 200 000 samples per second because of hardware limitations If you select Internal Timer the Trigger time controls appear and can be used to set the intervals at which recording starts Click the up and down arrows to increment or decrement the numbers or type values into the text boxes directly The internal timer requires fixed duration sampling When you start Chart recording the timer begins to count down the period set with the Trigger time controls and Chart records a block of the duration set with the Stop time controls When recording stops the timer continues counting down and the document s Title bar shows the message Recording waiting for internal timer and the time remaining When the timer completes counting down Chart repeats the cycle until the Stop button is clicked or the set number of blocks have been recorded For example if you set an interval of 10 seconds in the Trigger time controls and then set six seconds in the Stop time controls Chart would sample for six seconds stop and count dow
219. ng type Triangular Bartlett window Savitzky Golay least squares polynomial Polynomial degree 2 As with most channel calculations you specify a source channel in the Source channel drop down list Two smoothing methods are available a moving average with a triangular window and Savitzky Golay smoothing Chapter 6 Data Analysis 181 Moving average smoothing with a triangular Bartlett window works by taking the sample point together with a variable number of points on each side weighting the values according to a scheme detailed in Appendix C and averaging them to give the smoothed value at the sample point Savitzky Golay smoothing works by fitting a polynomial in a window around each sample point using least squares fitting You can specify the order of the polynomial from two a parabola to six Details on how the Savitzky Golay method works can be found in Reference 2 given at the end of Appendix C With both types of smoothing the number of points influencing each smoothed value is governed by the Window width Click the up or down arrows to increment or decrement the number or type in the number of points 3 2000001 for triangular smoothing 3 999 for Savitzky Golay smoothing in the text entry box The Window width is always an odd number Each smoothing method has its advantages over the other Moving average smoothing with a triangular Bartlett window is faster and computatio
220. nge dialog settings to values specified when you record or to open a dialog for the user to change settings when the macro is played If you want a macro that changes the settings in a dialog then select the dialog as you would normally while recording the macro Change the settings and then click OK in the dialog If you click Cancel changes made in the dialog are ignored When playing the macro the settings are changed without displaying the dialog When changing control values in dialogs absolute values are recorded not relative changes For example if you move a slider bar that increases voltage from 2 V to 3 V the new voltage 3 V is recorded not the change in voltage 1 V or the percentage change in voltage 50 If you want a macro that lets the user change dialog settings when the macro is played then while recording the macro hold down the Shift key when selecting the command that shows the dialog Do not make any setting changes just click OK When the macro is played back the dialog is displayed so that its settings can be changed by the user At that stage clicking OK or Cancel in the dialog lets the macro continue with the user defined settings or the original settings respectively Starting Sampling Macros can be used to control when sampling starts and stops If you click the Start button when recording a macro the Macro Sampling dialog will appear Figure 7 12 In general you would probably want to stop t
221. nnel Drag in channel Extend selection in a channel Shift click in channel Select tull height of a channel Alt drag in channel Select area of additional chan Shift drag in additional channel nel Select full height of additional Alt Shift click in additional channel channel Select area over all channels Drag in Time axis Extend selection over all chan Shift click in Time axis nels Deselect selected channel Shift click in channel Select a block Double click in Time axis 226 Chart Software Table A 4 Chart display shortcuts Table A 5 Miscellaneous Chart shortcuts Display Action Shortcut Revert shifted or stretched vertical scale Cycle through scale display modes Drag from anywhere on vertical scale Stretch from anywhere on vertical scale Hide split bar show Chart win dow with one pane Give each channel the same area Miscellaneous Action Start stop sampling on most systems Stop macro playing Special access to dialogs Menu Save As etc Add information on a data point to Data Pad Make channel specitic comment while sampling Make non specific comment while sam ling Send Marker home Double click in Amplitude axis Double click repeatedly in Ampli tude axis Shift drag in Amplitude axis Ctrl drag in Amplitude axis Double click split bar Double click any channel separa tor Shortcut Cirl
222. nnel here aa Bandstopt Chapter 6 Data Analysis 15 Entering an Expression To enter an expression click in the expression text entry box and type or click the various buttons and choose channels and functions from the drop down lists For channel data type Channell or Ch1 etc case is unimportant but no spaces should be used or choose a channel from the Channels pop up menu For functions choose a function from the Functions pop up menu or type the text of the function as it appears there case is unimportant Any combination of channels functions and operations can be entered The normal order of operations applies and brackets should be used as appropriate 4 9 6 gives 42 4 9 6 gives 60 If you enter a simple arithmetic operation say 4 9 6 without references to channel data or time you will get a straight line in the channel logging the result By default Arithmetic operates on the displayed data of the channels you specify The data in these channels may be calculated by other channel calculations for instance smoothing may have been applied You can choose to work on the recorded data of a channel input ignoring any other calculations that may be active by typing R before the channel expression RChannel1 or RCh1 or choosing from the Recorded Data submenu in the Channels pop up menu The recorded data is the signal that comes from the e corder to Chart before any channe
223. nsity show the power or amplitude per unit frequency Density is calculated by dividing the computed values 154 Chart Software Figure 6 14 An FFT displayed as lines bars and connected points by the width of each horizontal frequency bin this width narrows as the frequency resolution increases and a greater number of discrete frequencies are recognized The units of power density are y axis units Hz and the amplitude density units are y axis units Hz The square and square root are written as sq and sqrt in the axis labels The Log of Power and Log of Amplitude options show the power and amplitude spectra as true logjo values The logarithmic display makes discernible smaller components that might otherwise be difficult to see in the graph because of a large dynamic data range The Power Attenuation and Amplitude Attenuation options give a logarithmic display showing the relative attenuation of spectral lines with respect to a reference value Pmax for a power spectrum Amax for an amplitude spectrum The reference value is always taken as the largest value in the spectrum and shows as O dB Power attenuation is calculated as dB 10 logjo P Pnq and amplitude attenuation as dB 20 logjo A Amax Where P is the ith power component and A is the ith amplitude component Display as FFTs are often drawn as bar graphs with a vertical line or bar for each data point You can use this drop down list to
224. ntly recorded data Computed Input Click the Computed Input column to open the Computed Input dialog box Figure 6 33 p 184 This is the same as choosing the Computed Input command from a Channel Function pop up menu Figure 3 3 p 48 The dialog box lets you choose to process signals as they are recorded converting the raw data from any input into computed data Raw Data means the sampled data with no computed function applied and is the default setting The channel entry displays the computed function being applied if any and the input from which the raw data came The column is a useful way to check what is going on in each channel Color The drop down list in the Color column simply lets you select the color of the data trace in a channel Style The drop down list in the Style column lets you select the thickness of the data trace and whether the data points are displayed joined by lines or as unjoined dots in the Zoom View Calculation The drop down list in the Calculation column lets you apply calculations to channels of recorded data The options are the same as those in the Chapter 3 Setting Up Chart 61 lower half of a Channel Function pop up menu No Calculation is the V Refer default setting and means the displayed data in the channel are Chart Extensions recorded data with no extra calculation applied Chart extensions such p 218 as Shift can add extra channel calculations The calculations do not
225. nts will be printed on the data trace and as a numbered list following on from the end of the data printout If a selection is being printed only comments in that selection will be included Print range This panel is available when printing from the Data Pad The Print dialog lets you select a page range when printing the Data Pad The Data Pad is printed out looking much like it does on screen but empty columns are not included in the hard copy If printing takes a while a small dialog appears Figure 5 21 Click its Cancel button to stop printing You can cancel from Windows as well click the taskbar s Start button and choose Printers from the Settings menu Double click the printer you are using in the window that appears to see what is being printed and cancel it as required Printing Now printing Un named on the Auto HP Laserdet 4050 Series PS You can print while sampling at slower rates If you split the data display area of the Chart View you can make selections in the left hand pane and then print the selection itself or the Zoom or XY Views of it With all printouts Chart includes a footer on each page consisting of a separating line beneath which are the date and time of printing the Chapter 5 Working With Files 12 v Refer The Notebook Window p 156 Figure 5 22 Comment entry during recording computer user s name if it is in the system already for network use and the page nu
226. o 20 of cut off frequency forces df to be 20 of the cutoff frequency regardless of the intensity of the computation involved User defined allows any value of df to be specified in the Transition width text box within limits specified in Appendix C Initial Online Delay The initial online delay shown is the time it will take after sampling starts based on the currently set sampling rate for the filter to generate 176 Chart Software V Refer The Digital Filter Calculation p 242 Figure 6 27 The Integral dialog any output The value of the delay depends on the value of the filter transition width df and updates if df is changed Filter Length and End Effects Filter length is the number of samples in the window that is used to calculate the filtered output sample for each input sample point Filter length in seconds is the same as the initial online delay shown in the Digital Filter dialog Because Digital Filter relies on a window of points like other channel calculations such as Derivative there are end effects at the start and end of each data block The end effect regions are half the filter length Details of how Digital Filter calculates samples in these end effect regions are given in Appendix C Integral The Integral calculation provides the ability to calculate time integrals both online and offline and allows the integral to be reset to zero by events threshold crossings of a signal in
227. o make the cross disappear and then data shown on screen will be recorded normally Chart may be recording but nothing visible is happening This happens when Chart is reviewing rather than scrolling The Chart View Title bar will read Recording data after the document title and the Scroll Review button at the bottom right of the Chart View to the left of the Compression buttons will be highlighted depressed e Simply click the Scroll Review button to record normally You may be sampling at a very slow rate with a highly compressed horizontal scale so that it takes a long time for data to appear e Check sampling rates and Compression buttons and change as needed The Trigger may not be set to User and Chart may be waiting for a trigger event in this case the Chart View Title bar will read Recording waiting for trigger or similar after the document title e Choose Trigger from the Setup menu and set the Event in the Trigger dialog to User or supply the trigger event Macro Problems Macros behave unexpectedly e Make sure that you have the right macro not a different one of the same name in the case of name conflicts the latest macro loaded into memory is used e Check that you have the steps and effects recorded somewhere and that you haven t remembered them incorrectly it is very easy to do e f the macro is a new one it is possible that a step was not recorded correctly and in particu
228. o the file Channel settings When the Channel settings checkbox is selected then recording settings such as range and sampling rate are included as Chapter 5 Working With Files 105 lines in the text file at the beginning of the file and at such times as changes have been made to these settings Out of range data These option buttons allow you to choose how to handle outof range data sample points whose amplitude exceeds the channel range Outof range data values may be clipped set to the maximum or minimum value allowed by the range or output as NaNs Not a numbers which are recognized by some applications Reduction By default the text includes a data point for every sample in the file You might not want all this detail for instance if you have recorded something at a very high sampling rate and there are too many data points for your graphing application to cope with By entering a number other than 1 the default in the Reduction box you can choose to use fewer samples If you enter 2 the text would include the data points for every second sample if you enter 3 the text would include the data points for every third sample etc Comments are not lost even if the particular data points they were attached to are not included U S regional settings Selecting this checkbox is equivalent to choosing English United States in the Windows Control Panel replacing any other regional number time and date form
229. o understand how macros work they record the results of your actions not individual keystrokes and mouse clicks and record the simplest possible interpretation of those actions Even if you spend some time fiddling with control settings during the recording of a macro only the final settings you obtain will be used Macros cannot be edited and may be incompatible between different versions of Chart You should keep a written record of the steps involved in your macros and their purpose it is easy to forget which macro does what when you haven t used them for a few weeks Noting the steps down before actually recording will help when constructing complex macros since it can prove easy to miss out a step or end a repeated sequence in the wrong place with detrimental effects Macros are saved as part of a document and are available when that document or one of its windows is active When a file is saved all currently available macros are saved with it becoming part of the file Recording a Macro To record a macro choose Start Recording from the Macro menu or type Ctrl R the menu command then changes to Stop Recording When a macro is being recorded for the most part Chart remembers rather than executes operations but opening files changing input ranges or turning inputs off for example are done as you record During the process a Recording Macro message is shown in the Status bar to remind you that your actions are
230. od of selection e 0 1 seconds a You cannot nest this command within itself but you could nest it within the Repeat Select Each Block command say if you wanted to copy the mean of a channel for each ten second period in a block to the Data Pad and write the data of each block to a new file You should specify an End Repeat command after the instructions you want performed in the repeated sequence Repeat Select Each Block This macro command allows you to perform some operation on each block of data in turn in the Chart file For instance you may want to get the mean of a channel for each block and copy the information to the Data Pad When this macro command plays it will select and highlight each block in the file in turn As with all Repeat macro commands you should specify an End Repeat after the instructions you want performed in the repeated sequence Begin Repeat The Begin Repeat macro command is used to repeat steps in a macro You can repeat any group of commands up to 100 000 times You should specify an End Repeat command after the instructions you want performed in the repeated sequence When you choose Begin Repeat 216 Chart Software Figure 7 19 The Macro Repeat dialog from the Macro Commands submenu the Macro Repeat dialog appears Enter the number of times you wish the following group of commands to be repeated and click OK Macro Repeat Repeat count Cancel End Repeat
231. od pressure or respiration rate The results you get from the mean are the same as if you selected an exact period of the source integrated that selection and then divided by the period Calculations work from the first to last cycles in each block Minimum and Maximum The cyclic minimum function displays the minimum value found within a cycle The cyclic maximum function works similarly except that the maximum value of a cycle is shown Height The cyclic height function calculates the difference between the maximum value and the minimum value in a cycle 1 3 Max 2 3 Min The 1 3 Max 2 3 Min function adds for each cycle one third of the maximum amplitude of the waveform to two thirds of the minimum to give a form of approximate weighted mean It has been used as an estimate of average blood pressure mean arterial pressure This function should not be confused with a true mean more accurate information can be obtained using the Mean function It is provided for compatibility with historical results and to check the estimates made by some manual calculations Integral The integral function measures the area under a waveform calculated as the sum of the data points multiplied by the sample interval The integral over time of a signal with equal positive and negative summed values would be zero Minimum and Maximum Derivative The derivative functions give the minimum and maximum first derivative values with respect to time in
232. oe eii sietni etui seriei oo center cieie eeter re cents Tee 200 miy Smoothed 19 pt Chapter 6 Data Analysis 183 Computed Input By default Chart samples and records a raw signal from a sensor transducer or amplifier However Chart has a number of computed input functions that allow such online processing of signals within the e corder unit For example it might be more useful to monitor the frequency of an oscillating signal rather than recording the raw signal itself The Computed Input dialog box Figure 6 33 lets you process signals as they are recorded converting the raw data from any e corder input into computed data Both raw and computed data are displayed there for optimal settings adjustment The dialog box appears if you choose Computed Input from a Channel Function pop up menu or click the Computed Input column in the Channel Settings dialog box The channel to which the dialog box applies is indicated in its Title bar Figure 6 33 Display Channel 2 for instance The Computed Input dialog box click OK to apply the changes to the channel in the Chart View Channel number for Choose the e corder Computed Function the computed aa input for raw data here pop up menu x Raw Data Input Function Fiatemeter 5 76 mv uf 72 2 imin ir Computed Input for Display Channel 1 Sensitivity 100 control o E D Ka 50 a Ay on S a0 Threshold eal n A adi
233. ointer changes to an l beam over text in a single selected row and the text can be edited normally The channel identifier comment number and time cannot be altered If the Delete button is clicked a selected comment is deleted To choose multiple comments at the same time for deletion Shift click to select consecutive comments or Ctrl click to select or deselect multiple comments individually To copy selected comments to the Clipboard as tab delimited text including all visible columns choose Copy from the Edit menu The copied comments can then be pasted into other applications Chapter 5 Working With Files 125 If a comment is selected and the Go To button is pressed the Chart View becomes active the comment is located and centered in the data display area and an animation draws your attention to the comment box This is very useful for locating commented features in the file As a shortcut you can double click a comment to go to it as well If you have multiple comments selected the comment at the top of the selection is the one centered in the data display area If Chart is sampling then the comment is only located and centered if the Chart View is in Review mode If the data display area is split into two panes comments are located and centered in whichever pane is in Review mode or in the right hand pane if both are Comment Numbering When comments are deleted the numbers for the remaining comments in a file do
234. ommands conventions 9 menus 221 224 altering 202 204 creating 208 hiding 203 locking 203 Menus dialog 203 Menus command 202 Message command 214 Minimum Point command 131 monitoring 36 most recently used files list 27 222 Multiple Add to Data Pad dialog 139 multiple e corders 73 75 N NaN 106 navigating 30 network 41 New command 25 New Data Pad Miniwindow command 141 New Document dialog 25 New Macro dialog 208 No Calculation command 158 noise 18 nota number 106 161 Notebook command 156 Notebook window 156 157 printing 157 number of channels appearing 48 62 number of channels on 48 Nyquist frequency 14 O OLE Linking 107 109 Open dialog 26 Open command 26 opening a Chart file 24 optimum performance 41 out of range data 17 106 out of range Data Pad value 136 overlaying in Zoom View 89 overview of Chart 22 24 P Page Layout dialog 120 page setup 118 Page Setup dialog 118 Page Setup command 118 Paste At End command 104 Paste command 104 pasting Chart data 103 Period computed input function 191 Play Sound command 213 270 Chart Software Playing Macro dialog 209 pointer 34 cross 130 double headed arrow 99 130 dragging 81 heavy cross 136 l beam 34 resizing 125 137 separator 78 split 79 stretching 81 post triggering 65 preferences 200 206 Preferences submenu 222 Controls command 204 Cursor command 205 Data Buffering command 4
235. on allows you to adjust the Amplitude axis directly to display a desired range of values just as you can with the Set Scale dialog available from the Scale pop up menu in the Chart View The scale will affect the accuracy in significant figures of the displayed numbers Channel calculations in Chart use single precision floating point arithmetic so results are accurate to six decimal places The number of 164 Chart Software decimal places set in the dialog from O to 6 affects only the display not the internal accuracy of the calculation Using Unconverted Voltages Signals in volts millivolts or microvolts i e without units conversion applied are all dealt with by the Arithmetic calculation as if they are in volts This means care must be taken when using lower ranges and when dealing with data recorded at ranges with different orders of magnitude Depending on the data and the operations performed the numbers calculated may be very large or very small They can be adjusted to be easier to use by using a scaling factor in the expression In general you have to work out what you want the results displayed in and apply an appropriate scaling factor to the expression 1000 if the data are to be in mV or 1 000 000 if the data are to be in pV For example if you recorded two signals on differenet channels using the the 10 mV range and used Arithmetic to add a two such channels together the results would be expressed in
236. on of measurements Smoothing can help to reveal a signal buried in noise or to reduce triggering the detection of cycles as a noisy signal passes through a threshold Selecting the Smoothing checkbox displays the smoothed signal as a black waveform in the signal display area You can change the period of the smoothing window using the text box or slider the effect of your changes can be observed in the signal display area The differentiated signal can be used for baseline tracking by triggering cycle detection from the slope of a peak rather than the absolute height of the peak which may be drifting over time Selecting the Differentiate checkbox applies a derivative calculation with a window size of three points The derived waveform is displayed as a black waveform against Choose the measurement to be calculated Cycle marker and displayed in the Chart channel Cyclic Measurements Channel 2 Output Source Channel 1 Nj Scale auto Scale Measurement Rate v di i ih t NaICaTes NMa Preview of Detected Cycles these detection 2 e Q 2 2 00e 04 F 500 settings are 400 min hpr j shared with i y 0 00e 00 P n 300 Signal display l other channels area 200 2 00e 04 or Data Pad 100 i columns L 4 00e 04 0 if m i 100 6 00e 04 Preprocessin lt i gt 20 1 a Eq p gt i J F Gi Review and ae ngs May Cycle Detection Preprocessing shared Detection Paramet
237. one of the other waveforms the display shows relative times but absolute amplitude values Comments from the Chart View are visible in the Zoom View Settings made in the Display Settings dialog Figure 4 4 affect the display of comments in the Zoom View as they do in the Chart View but the comment pop up box Figure 5 24 is not available Adding data to the Data Pad when the Zoom View is active adds relevant data from the selection that is shown in the Zoom View If the selection in the Chart View is discontinuous straddling two or more blocks then the blocks are also shown in the Zoom View unless you have chosen to turn off the display of lines between blocks in which case there is a thin gap shown 90 Chart Software Figure 4 12 DVM miniwindows for Channel 1 and Rate Time Printing and Copying When the Zoom View is active then the Print option in the File menu changes to Print Zoom View and if the command is selected the contents of this window are printed rather than those of the Chart View The Zoom View can also be copied as a picture for pasting into other applications by choosing Copy Zoom View from the Edit menu Displaying Digital Read outs The DVM submenu of the Window menu provides a digital voltmeter for each channel hence the name and read outs of the sampling time and date in the form of resizable miniwindows The miniwindows can let you keep an eye on recorded values from the othe
238. ontrols are inactive The active controls in the dialog change with the chosen mode You can turn stimulation off or on without losing the values you have entered The Stimulator Panel Setup gt Stimulator Panel lets you turn on and off and adjust stimulation while sampling Chapter 3 Setting Up Chart 07 Figure 3 13 The Stimulator dialog for pulse mode Choose between Choose between pulse Choose a channel in continuous stimulation and and step stimulus modes which fo mark the stimulus a set number of pulses Set the number of pulses Stimulator Document StinNlator made a Set a delay Output Continuously Marker channel between clicking the Start or Stimulate button Set number of pulses When recording starts Delay oo B ms O Manually Stimulate Range PPM Hz Output range Cleto sare Frequency is3 asa3aHe H Amplitude stimulus when Manually start mode is chosen I Baseline Rise hye aw Oe Aca Values set by the various controls dedielaged an the text entry boxes I Use the slider bars or text entry boxes to set stimulus parameters Stimulator Mode The Stimulator mode drop down list lets you choose the stimulus type Pulse or Step Once one is chosen you can use the dialog controls to define its characteristics precisely Pulse This setting generates a rectangular pulse stimulus that starts at a baseline voltage is raised or lowered to the set amplitude for the p
239. open Chart files that have somehow lost the suffix that identifies them This filename suffix or file extension is always present in Windows although you can choose to hide it Using a demonstration file as you work through this manual will show you some real data and perhaps give a better idea of what is going on in Chart If you want to protect the original files duplicate some demonstration tiles and rename them and open the renamed files to experiment with 26 Chart Software The four most recently opened Chart files are listed at the bottom of the File menu You can reopen a file in the list by selecting it from the menu or by using Alt the list number as a keyboard shortcut If you select a tile that is already open it is maximized and brought to the front Closing a File or Exiting Chart To close a Chart file choose Close from the File menu This will close all of the file s associated document windows You can close the document windows individually in this case a file will not be closed until the last Vv Refer document window associated with it is closed The Experiments Gallery pees Note that when the last file in Chart is closed the Experiments Gallery dialog see Chapter 5 will appear provided that it has been set up To exit Chart that is quit the program and close all its windows choose Exit from the File menu click the close button of the Chart Application window or type Alt F4 In either case
240. ops to 37 1 e of its initial value over the set time up to 65 seconds This avoids drift and sudden resets but the resultant integral will be inaccurate this inaccuracy increases as the time constant entered in the Time text box gets smaller Original signal Integral with timed reset Integral with time constant Chapter 6 Data Analysis oF 198 Chart Software CHAPTER SEVEN Customizing amp Automating Chart can be simplified or modified by locking hiding or altering menus and menu commands Macros that speed up and automate complex tasks such as detecting all the peaks in a file and logging statistics about each one to the Data Pad can be added to existing or new menus Chart extensions add further functionality such as the ability to export files to other data analysis applications or the ability to analyze recordings This chapter looks in detail at Chart preferences and macros and introduces Chart extensions Chart Software 199 V Refer Software Updates p2 Figure 7 1 The Default Settings dialog Preferences The various options in the display settings and recording controls allow basic customizing of Chart You can also choose to lock hide or alter menus and menu commands and their keyboard equivalents This can be particularly useful in simplifying Chart for teaching purposes The commands in the Edit menu and its Preferences submenu let y
241. or Figure C 1 A selection of 968 data points with FFTs of 256 no overlap divides into 3 FFTs with 200 left over so Spectrum adds 56 zeroes at right to pad out data for the fourth FFT chosen in the settings or if not enough points exist within a data block the remainder is padded with zeroes which are added to the right side of the remaining data points of the selection before the transform is applied The Spectrum window shows selection information above the graph area the number of FFTs the number of data points per FFT and either the number of padded points if any or whether the selection was adjusted to give an integral number of unpadded FFTs This information changes with Spectrum s settings Selection 968 data points 256 256 256 200 p FFT FFT FFT FFT Average 56 padded zeroes Display Spectrum s Implementation of the FFT The treatment here is only a summary see Press et al for a more complete discussion Chart takes samples at discrete intervals set by the sampling rate If we look at a sequence of N consecutive samples where N is an even number for simplicity with a sampling interval A we can define a function hg h t where the time when sample k is taken t kA and k is the series O 1 2 N 1 It is assumed that the function that describes the sampled points is representative of the entire waveform that is that there is some form of periodicity The FFT transforms these N disc
242. orders as usual When the miniwindow is resized the text changes size so you can expand it to enable it to be read more easily to keep an eye on recorded values from the other side of the room for instance Click the body of the miniwindow to access its Data Pad Column Setup dialog again Its Title bar contains its column label and heading to indicate what it displays Data Pad miniwindows can also be displayed by choosing the New Data Pad Miniwindow command from the Window menu or by clicking the Data Pad Miniwindow button on the toolbar This will display a Data Pad miniwindow for the first column whose miniwindow is not already displayed B Channel 1 Mean EJ 2 033 V Statistics Mean calculates the mean of the data points in the selection or returns the value at the active point Standard Deviation calculates the standard deviation of the data points in the selection Standard Error calculates the standard error of the mean of the data points in the selection Number of Points returns the number of data points in the selection zero for an active point Maximum Value returns the value of the largest data point in the selection Time at Maximum returns the time at which the largest data point in the selection was recorded Minimum Value returns the value of the smallest data point in the selection Time at Minimum returns the time at which the smallest data point in the selection was recorded Maximum Minimum calculates the di
243. ormal distribution with a mean of 0 0 and a variance of 1 0 Note that with these two functions an argument is optional The argument is a seed parameter which varies the point at which the random number sequence begins and can be any number from zero up to just over 2 000 000 000 if you enter a non integer number it will be rounded down to the nearest integer thereby specifying a point in the random number sequence Other Functions The function Sign returns the sign of a number that is Sign x 1 if x gt 0 1 if x lt O Abs returns the absolute value of a number that is negative numbers are made positive Sqrt returns the square root of a number Pi simply applies the constant T approximately 3 1415927 when used in an expression SampleTime returns the time in decimal seconds from the start of the data block Round rounds a number to the nearest whole number 0 5 rounds up Int returns the integer part of a number truncating any fractional part regardless of sign For instance Int 2 999 will return 2 Mod returns x modulo y the remainder of x y The two arguments are separated by a comma for example Mod Ch1 Ch2 Threshold requires two arguments and returns 1 when a gt b otherwise it returns zero Window requires three arguments and returns 1 whenever both a gt b and a lt c otherwise it returns zero Threshold a b Windowla b c 162 Chart Software Channel Calculation Fun
244. ou manage aspects of Chart s behavior and data display such as default settings menus and cursors You can also access the License Manager which lists all your current licenses generally you will only have one license for Chart and allows you to add and delete licenses Data buffering is discussed on page 41 Default Settings When new Chart documents are created on starting Chart if you don t start up from an existing Chart document and when the New menu command is chosen they have certain base settings such as the sampling rate input ranges the number of channels that appear and menu configuration To alter them or revert to the original settings choose Default Settings from the Edit menu to open the Default Settings dialog Default Settings The Default Settings are used when you start Chart and can be used bo create new documents Revert to program defaults Save settings From document Waveforms as Biia the Default Settings Click the Save button to use the settings in the active document as customized default settings for new Chart documents Customized default settings are stored in a Chart settings document called default in the same folder as Chart Click the Revert button to use the factory original factory default settings of Chart with all channels having a 10 volt range and so on some settings depend on the attached e corder 200 Chart Software Figure 7 2 The License Manager dia
245. ough the open windows making each active in turn type Ctrl Tab or Ctrl F6 Note that the windows are titled so that you can tell which belongs to a particular document in the window s title the name of the file is followed by a colon then the name of the window For a file named pHandtemp the main Chart View would be titled oHandtemp Chart View the Zoom View pHandtemp Zoom View etc The toolbar buttons for Chart Zoom and XY Views make active the appropriate window of the active document To clean up windows in Chart choose Cascade or Tile from the Windows menu Minimized windows are not affected by either of these menu commands The Cascade command neatly lines up all open windows with their Title bars showing each offset a little from the previous one Figure 4 13 The Tile command divides up the space in the application window equally between all open windows Figure 4 14 If you have more than a couple of windows tiling them might make them too Chapter 4 Data Display 93 Figure 4 14 Tiled windows in Chart squashed to be of much use the command is more useful to compare two windows or to expand one window to fill the space available without actually maximizing it the Chart document window fills the space available like this by default when Chart is first started up If you have minimized windows in the Chart application window you can line them up neatly at the bottom of the window by
246. our signals on a single e corder with enough inputs 74 Chart Software Maximum Sampling Rates There are practical limits on maximum sampling rates and the number of channels you can use when using multiple e corders These are imposed by performance limitations of the computer and or the USB interface Chart cannot determine these limitations in advance and sampling will stop in one or more documents if the system fails to keep up with the sampling requirements If high sampling rates are required on multiple e corders try the setup in advance to ensure adequate system performance Experimenting with sampling rates in excess of what is actually required will give an indication of what is possible Note that using other applications while Chart is sampling will limit Chart s performance and may cause one or more documents to stop sampling if running close to system limits Other applications can use signiticant processor time when running in the background so if you are having problems try exiting other applications including screen savers and email packages Chapter 3 Setting Up Chart 73 76 Chart Software CHAPTER FOUR Data Display Chart allows you great flexibility in displaying data You can change the lines patterns and colors of the data display You can expand or reduce the horizontal and vertical scaling split the screen change the size of each channel s display or hi
247. p down list and work your way through printer specific features by clicking the Properties button Print Command Active View or What Prints Table 5 1 Window Rang reounenes Print Chart View Chart The whole file Print Selection Chart The selected area Print Zoom View Zoom Zoom View contents Print XY View XY XY View contents Print Comments Comments List of comments in file Print Data Pad Data Pad Data Pad contents Print Notebook Notebook Notebook contents Print Spectrum Spectrum Spectrum window contents Open the Page Layout Figure 5 19 A The Page Layout dialog Printer HP LaserJet 4000 Series PS 4 dialog from C keep shape he re Drag the image to position it on me page Deselect this checkbox to reshape the image Drag the gray l vat borders to resize tesini Page the image boundaries 120 Chart Software Figure 5 20 The Print dialog the options depend on what is being printed Figure 5 21 The Printing dialog Printer Name Auto HP Lasewet 4050 Series PS on JOE SH Properties Status Ready Type HP LaserJet 4050 Series PS Where WJOES Printer2 Comment Print to file Options Copies V Print Comments Number of copies f JAGE Cancel Print Comments This option is available in the Options panel when printing from the Chart View either the whole file or a selection If it is selected comme
248. pare them with Table 1 on page 225 See below for resetting procedures Menus controls or settings don t resemble those in this manual You started Chart by opening a data file with custom settings or a Chart settings file e Start up again from the application itself choosing Chart from the Programs menu of the taskbar s Start button or double clicking the program icon from wherever it was installed Chart s default document has been altered e Choose Default Settings from the Edit menu and click the Revert button in the Default Document Settings dialog that appears New Chart documents can then use the defaults originally set in Chart with all channels having a 10 volt range and so on some settings depend on the attached e corder until the default settings are changed again 232 Chart Software You can customize the settings in the default document yourself and create your own Chart settings files to ensure that you have the settings menus and macros that you want I ve altered menus and locked myself out can t save etc Type Ctrl or Ctrl Shift 1 to open a dialog that allows special emergency access to the Menus and Save As dialogs etc Recording Problems keep getting alerts saying the sampling rate is too fast Chart has a maximum continuous sampling rate of 200 000 samples per second Lower rates apply when more channels are used The external trigger can t be used at a sampling rate o
249. pears It gives you the choice of using the default settings or using the settings from the active open document If the checkbox is selected then before the new document appears the Hew Document Create a new document using Default Settings Close Documenti after creating the new document Chapter 2 Introduction to Chart 25 Figure 2 4 The Open dialog V Refer Opening Text Files p 109 Look in Demo Files v ar ee Ej g Mechanical vibrations My Documents E Mo Computer a File name Mechanical Vibrations w biy Network Files of type eD AQ Chart File edcht edset w active open document is closed you get to save any changes made to it New documents are titled Document1 Document2 etc Choose Open from the File menu to open an existing file The Open dialog appears Use it to find the file on your computer that you want to open Once you select the file in the dialog list it highlights its name appears in the File name text entry box and clicking the Open button will open it The Files of type drop down list lets you choose the sort of file to open only the chosen type will be visible in the scrolling list The standard choices in the drop down list are Chart Data File Chart Settings File Chart File the default which includes both data and settings files Text and All Files but others may be added in some circumstances The All Files option allows you to
250. pen and proceed 12 Chart Software Basics of Data Acquisition This is a general introduction for those new to data acquisition It should help you to obtain the best results when recording with an e corder system The purpose of the e corder system is to acquire store and analyze data Figure 1 4 summarizes the acquisition Usually the raw input signal is in the form of an analog voltage whose amplitude varies continuously over time This voltage is monitored by the hardware which can modify it by amplification and filtering processes called signal conditioning Signal conditioning may also include zeroing for example the removal of an unwanted steady offset voltage from a transducer s output After signal conditioning the analog voltage is sampled at regular intervals The signal is then converted from analog to digital form before transmission to the attached computer computers need digital data The computer software usually displays the data directly it plots the sampled and digitized data points and reconstructs the original waveform by drawing lines between the points Digital data can be stored on disk for later retrieval Software can also easily manipulate and analyze the data in a wide variety of ways Most of the parameters that affect acquisition can be set by the user Fi through the software To make a good recording the parameters must igure 1 4 n A graphical summary of be appropriate for the signals be
251. periment and the Stimulator Panel page 72 allows this to be turned on or off or adjusted as required during recording A range of channel calculations page 158 can be applied to further analyze displayed data for example data can be smoothed to remove unwanted high frequencies in the waveform Chapter 2 Introduction to Chart 23 Figure 2 1 Chart data and settings file icons Data File 7A Hiz Settings File Customizing Chart can be extensively customized page 199 for your purposes Controls and menus and their commands and keyboard shortcuts can be locked hidden or altered page 202 and Chart as a whole simplified say for student use Chart files and related files such as documentation and multimedia files can be added to the Experiments Gallery page 96 for easy access Macros page 206 can be created to speed up and to automate complex or repetitive tasks and stored in any menu in a file Customized menus units and macros are document specitic Chart extensions page 218 are available to add specialist analysis capability to Chart and to provide data export options to other applications Chart Files There are two main types of Chart file data files and settings files Figure 2 1 Data files are used for recording data Settings files do not contain recorded data but store Chart settings such as sampling rate input ranges trigger settings and display settings They can be used to create new dat
252. phase reverse a repetitive signal The moving average option in the Smoothing calculation therefore weights the points with a triangular Bartlett window the central point affects the result most strongly with points further away affecting the result less and less For 3 point smoothing the weights are 1 4 1 2 1 4 for 5 point smoothing the weights are 1 9 2 9 1 3 2 9 1 9 etc 244 Chart Software End Effects Each smoothed value is calculated from a range of preceding and following sample values The calculation cannot therefore be applied to points that are too close to the start or too close to the end of a data block The Smoothing extension replaces such points by a constant value equal to the nearest smoothed point Thus with a Window width of 255 the first 128 points of a data block will all have the same smoothed value and similarly for the last 128 points of a data block References 1 A V Oppenheim and R W Schafer Discrete Time Signal Processing second edition Prentice Hall Upper Saddle River New Jersey 1998 2 W H Press et al Numerical Recipes in C The Art of Scientific Computing second edition Cambridge University Press Cambridge Massachusetts 1994 Measuring Signal Slopes The slope or first time derivative of a signal is its rate of change If the signal represents position or displacement then its slope is velocity If the signal represents volume then its slope is flow
253. play which has zero at the bottom of the display area Note that this shortcut does not take units conversion into account if it is on then you may have to drag the scale to get the zero point to the desired location Display Settings The Display Settings dialog lets you choose the form and units of the Time axis whether blocks and comments are marked whether the date is displayed in the Chart View window and whether data is displayed scrolling from right to left or in sweep mode You can also use it to change the color and form of the graticule the display grid in the Chart Zoom and XY Views and to choose the color and line style of the trace drawn in the XY View Choose Display Settings from the Setup menu to open the dialog Time Format The Time format controls let you choose the form and units of the Time axis This applies to the whole axis and can be changed at will just by using the dialog since all time information about a recording is stored The time at the pointer position along the Time axis shown in the Rate Time display will be in the form chosen here 82 Chart Software V Refer Deleting Data p 102 Note If you record new data in old files and choose From Start of File you might end up with very large numbers towards the right of the Time axis If you append data from different files you could even get negative times Check the Date display for the dates of recordings Figure 4 4
254. plifier dialog l Input 1 Range Range options Low pass o Low pass filter options AMEE MAHE at MEn Tp v Single sided Signal input T Differential controls ilt A e l Filtering options Mains Filter E a a 200 invert Signal polarity 50 Chart Software V Refer The Amplitude Axis p 79 V Refer Digital Filter p 173 The Input Amplifier dialog appears when you choose Input Amplifier from the Channel Function pop up menu or click the Input Settings column in the Channel Settings dialog By default Chart channels record data from the corresponding e corder inputs To set up the inputs quickly click the arrows by the dialog title or press the right or left arrow keys on the keyboard to move to the Inout Amplifier dialogs for the adjacent channels This skips channels that have their inputs turned off Click OK to apply the settings shown in the dialog Signal Display The input signal is displayed so you can see the effect of changing the settings no data are in fact recorded when setting up the input amplifier Slowly changing waveforms will be represented quite accurately whereas quickly changing signals will be displayed as a solid area showing only the envelope shape of the signal formed by the minimum and maximum recorded values The average signal amplitude is indicated by a horizontal dotted line and its numeric value is shown at the top left of the display area You can stop the signal sc
255. ply incorporate one or more of them in the macro that needs them You might wish to have three beeps signal when the e corder starts recording data or a bell and a whistle when a trigger point has been reached You can even record short verbal cues if your computer has a microphone input and suitable software and use these in your macros If a macro step involves attempting to play a sound that is no longer present created on a computer with a different setup or since removed from its original location then the sound will not be played Chapter 7 Customizing amp Automating 213 Figure 7 16 The Macro Message dialog Message If you select the Message macro command the Macro Message dialog appears This allows you to cause message boxes requiring user response to appear at certain stages within the macro You can type in the message of your choice as many characters as fit in the text entry box The message box produced will have an OK button and if the Show Cancel button checkbox is selected a Cancel button as well for exiting the macro When the macro is played back the computer should beep as the alert box appears Macro Message Message Type a message here Icon o A o G o 6 amp 3 There are three choices of icon which you can use to indicate the urgency of a message the middle one for information the exclamation mark for an important alert and the cross for something critical Click
256. quencies A band stop filter is generated by subtracting a band pass filter output from the input data Filter Length and End effects The effective length in number of samples of the FIR filter not counting reduction by the decimation factor if decimation is possible is given by 3 846 df Each block will begin and end with a number of samples for which the true filter output cannot be calculated due to the FIR filter window extending beyond the block boundaries The length of these end effect regions is half the filter length For low pass filters these samples are generated by repeating the first and last valid output samples in the block This results in a flat line at the beginning and end of each block High pass filters are generated by subtracting a low pass filter output from the input data so the end effect regions will consist of the constant value from the low pass filter end effect samples subtracted from the input data Similarly the end effect regions of narrow band pass filters are generated by repeating the first and last valid output samples in the block and the end effect regions for notch filters are generated by subtracting these two values for the narrow band pass filter from the input data Band pass filters are composed of a high pass filter followed by a low pass filter so the end effect samples will be generated accordingly at Appendix A Technical Notes 243 each stage The end effect
257. r transfer elsewhere To open the Data Pad choose Data Pad from the Chapter 6 Data Analysis 135 Figure 6 4 The Data Pad window Window menu You can leave the Data Pad visible and constantly updated but in the background or tiled with the Chart View Information on the current selection or active point is displayed just above and beneath the column headings the readings in the top row beneath the column headings are separated from recorded data by a heavy line this top row can be unfixed for editing though As data are added to the Data Pad new rows of values are created below existing rows in the data area Each cell contains only one entry the value added to the Data Pad at the time the calculation for its column was made The column heading shows the column label A Z then AA AB etc through to IV and the title of the channel from which the reading currently derives Use the scroll bars to move down through rows or across columns Note that NaNs due for example to out of range values in Chart are represented in the Data Pad as 1 4QNB and will be exported like this when the Data Pad is saved as a text file he Waveforms Data Pad utton A 92 points from t 2 1 to t 2 555 Pop up menu F E Cell Channel 1 ES Gion Standard Deviati Sanon Data on the p z current Column Ll6 i headi 1 1558 0 8563 0 00 01 68 selection eaaings D 1 1397 0 7698 0 00 02 195 0 5822 1 1098 0 00 02 555 Channeli Channel
258. r 5 Working With Files 109 Figure 5 9 A portion of a typical text file to be read into Chart with the time value and data readings for four channels at that time in each line Figure 5 10 The Open Text File dialog showing options in the Default Rate drop down list 2 055 0 4025 1 3275 0 28 1 2775 2 06 0 5975 1 365 0 1575 0 75 2 065 0 79 1 4025 0 035 0 165 2 07 0 9825 1 4425 0 085 0 425 2 075 1 1725 1 48 0 205 0 97 2 08 1 365 1 5175 0 325 1 42 2 085 1 5525 1 555 0 445 1 725 2 09 1 74 1 075 056 l 8779 Time values Data readings for Channels 1 to 4 information recording dates and times and comments as well Display settings apart from channel titles are ignored The Open Text File Dialog When a text file is selected in the Open dialog in Chart and the Open button is clicked the Open Text File dialog appears Figure 5 10 In it you must specify the form of the data that Chart is to read in Times in first column If this checkbox is selected the default then Chart will read the first column of the text file as time values and the Default rate drop down list is disabled Turn the checkbox off if there are no Open Text File Column interpretation Times in First column Default rate 100 fs a F Ignore non numeric lines Cancel 110 Chart Software times with the data In this case the Default rate drop down list becomes enabled and must be used to choose the sampling rate at w
259. r as you have the time to learn about the features you need We recommend that you gradually work through this manual in front of your computer It may take more effort in the short term but will end up saving you time and energy Working through a manual like this while slower is a more effective learning process than just trying an application on the computer and seeing what happens The information in the following chapters is set out in the order you will probably require it First of all though read the rest of this chapter which covers computer requirements installing your copy of Chart and the basics of data acquisition Chart Software Conventions Where convenient Menu commands shortcuts etc may be described using the conventions in Table 1 1 Note that shortcuts can appear in two forms hyphenated in text and with a sign in tables to make each clearer in context Example phrase Meaning Table 1 1 i Shorthand usages Edit gt Preferences gt Cursor The Cursor command of the Preferences referring to menu submenu of the Edit menu commands and shortcuts Ctrl S or Hold down the Ctrl Control key and type Ctrl S s Alt Shift click or Hold down the Alt and Shift keys and Alt Shift click click the mouse button Where to From Here This book is a reference manual It tells you how to use the software and how everything works but it does not include tutorials or extensive worked examples
260. r buttons at the bottom left corner of the window correspond to channel numbers and buttons for channels with no selected data in the Chart View appear dimmed A short bar of the color chosen for the channel waveform is displayed above the Channel Number button to aid identification You can repeatedly zoom in further on the data by making repeated selections in the Zoom View each time the selected data fills the window Once you have made multiple zooms you can navigate back and forth between views by using the History curved arrow buttons at the top left of the window or by using the arrow keys left and up for moving back through the zoom history and the right and down arrows for moving forward The Stacked View If the Stack button is clicked then the Overlay button is turned off and selected channels are displayed stacked one below the other in much the same way that they are displayed in the Chart View The height devoted to each channel is the same regardless of the proportion in the Chart View with channel titles and units shown at the left If there is not enough room to draw all the channels in this mode enlarge the Stack button selected Waveforms Zoom View Channel4 0 3975 E g B g Chapter 4 Data Display 89 V Refer The Amplitude Axis pr V Refer Measuring from the Waveform p 130 bi V Refer Using the Marker p 130 V Refer General Display p 84 Zoom View As in th
261. r during recording by dragging the vertical Split bar to the right Splitting the data display area allows the incoming data to be viewed alongside previously recorded data so that you can compare the two Note that there are separate Compression buttons for each pane so the data in each can be shown at different horizontal compressions There is also a Scroll Review button in each pane This means that while recording you can set either pane to Review and the other to z 6 6 5 4 a e 50 1 al gt E a 5 a Split bar Chapter 2 Introduction to Chart 39 V Refer Data Buffering p 41 Scroll In the Review pane you can check waveforms of interest make selections use the Zoom View XY View Data Pad and Spectrum window and even print selections You can use the Add Comment menu command to add comments to the previously acquired data there In the Scroll pane you can make comments on newly acquired data using the Comments bar Running other Applications while Recording You can run other applications while Chart is recording in the background A Chart View or the Chart Application window itself can be minimized and still record You will need enough memory RAM in your computer to be able to run multiple applications at a reasonable speed of course You need to watch that you aren t placing too many demands on the system Data buffering settings can also affect performance It helps if you have a fast comp
262. r side of the room for instance To open one choose a menu command from the DVM submenu or drag the Range Amplitude display for a channel the Rate Time display or if visible the Date display to tear it off The miniwindows are enlarged free floating versions of these displays and work just like them Channel 1 1 6850 V Rate Time EJ A DVM miniwindow floats in front of the active window can be moved around by dragging its Title bar even outside the bounds of the Chart Application window and can only be dismissed by clicking its close box It can be resized by dragging its borders as usual When the miniwindow is resized the text changes size so you can expand it to enable it to be read more easily The text will be the same color as the data trace in its channel to help to identify it or black for Rate Time and Date For the channel miniwindows the Title bar indicates the channel to which the miniwindow applies If the default channel title such as Channel 1 has been replaced the Title bar incorporates the channel name assigned in the Channel Settings dialog This channel name applies in the DVM submenu as well When recording the Rate Time miniwindow shows the time in the mode chosen in the Display Settings dialog Otherwise it shows the Chapter 4 Data Display 9 time at the pointer position if the pointer is over the data display area or Time axis or the current sampling rate in samp
263. rate because of aliasing An analogy to aliasing can be seen in old films spoked wagon wheels may appear to stop or even go backwards when their rate of rotation matches the film frame speed obviously not an accurate record To prevent aliasing the sampling rate must be at least twice the rate of the highest expected frequency of the incoming waveform This sampling rate is known as the Nyquist frequency the minimum rate at which digital sampling can accurately record an analog signal For example if a signal has maximum frequency components of 100 Hz 14 Chart Software Figure 1 6 Aliasing sampling a 3 5 Hz signal at 4 samples second gives a misleading waveform an apparent signal of 0 5 Hz however real life effects tend to be more subtle V Refer The Spectrum Window p 15 the sampling rate needs to be at least 200 Hz to record it accurately To provide a safety factor to guard against information loss it is usual to sample at five to ten times the highest expected frequency rather than the minimum two times Actual signal 3 5 Hz at 40 s Aliased ay 0 5 Hz at 4 s OR O 4 2 4 In most cases the highest expected frequency will be known It may well be limited by the transducer used a bridge transducer to measure mechanical force will not produce high frequencies for instance If you are unsure of the frequency range bandwidth of your signal a useful rule of thumb is to choose a sampling rate high enou
264. rent filter sharpness at the low and high frequency cutoffs For all six filtering functions a source channel and at least one cut off frequency two for Bandpass and Bandstop are required as parameters Filter sharpness is an optional parameter or parameters the default is the Auto adjust setting as described with the Digital Filter channel calculation Units and Scaling If Units Conversion is applied in a channel used in an expression Arithmetic ignores the units and just uses the displayed values in that channel for its calculations Note though that the linear scaling performed by Units Conversion may affect numeric values For this reason you will be alerted if a channel used in an expression has different units in different blocks Units conversion does not work in a channel where the Arithmetic calculation is active So that units can be provided for a calculated channel where you want them the Unit name text entry box lets you type in up to nine characters for a unit name By default the Auto scale checkbox is selected which causes Arithmetic to estimate the most appropriate scale for the channel when there is data to base a scale on If channel data and operations are unusual and the checkbox is deselected a scale can be assigned manually You can type in directly the lower and upper limits of the scale to be displayed in the Scale top and Scale bottom text entry boxes This deselects the Auto scale checkbox This opti
265. rete samples in time with h voltage or derived units to N discrete samples in frequency with H frequency amplitude The frequencies can be assigned the discrete values f n NA where n is the series N 2 N 2 1 The discrete Fourier transform of the N points hg is defined by 238 Chart Software H gt hpe2nikn N k 0 This transform maps N complex numbers hg into N complex numbers H for data measured from physical phenomena such as Chart deals with numbers hg are real with the imaginary part set to zero H are in the frequency domain since the horizontal axis is measured in units of 1 A which represents frequency Zero frequency corresponds to n O positive frequencies correspond to values 1 lt n lt N 2 1 The function can be seen to be periodic in n with period N with H_ HyN n for values of n other than zero If Re H and Im H are the real and imaginary parts of the nth frequency component of the FFT then P n the power modulus squared of the nth frequency component may be expressed as Re H Im H P n Adding the positive and negative frequency components gives p m the power of the mth frequency component of the spectrum p 0 P 0 p m P m P N m O lt m lt a Ny _ pf N 3 43 In the Spectrum window p m is shown in units of V2 squared volts or other squared units if Units Conversion is on The vertical axis of the Spectrum can also be shown as
266. rigger Seles Recording waiting for trigger shows while the e corder is waiting for a trigger event to occur before it starts sampling If you have set up a trigger delay Recording posttrigger delay shows after triggering while the e corder is waiting for the delay to elapse A few other messages may appear in some circumstances Adding Comments while Recording During recording comments can be entered as required and are automatically numbered as they appear The Comments bar at the top of the Chart View below the Title bar is usually used for this Type the comment in the text entry area Click the Add button at the right of the text entry area or press the Enter key to add the comment to the file at the time the action is taken By default comments apply for all channels when this is the case the numbered comment box is preceded by an asterisk Note that comments are reset to this default whenever sampling is started To comment on a specific channel either select the text in the Channel field and type the number of the channel or click the channel you wish to comment on in the data display area To apply a comment to all channels type in an asterisk or click in the Time axis area at the bottom of the Chart View You can also click the small up and down arrows while recording to change channel numbers Channel 1 Channel the comment Comment Text is inserted here as Click this button to applies to
267. ring Data buffering allows you to choose where data will be stored while recording and how disk buffering is done This affects whether files in the process of being recorded can survive power failures crashes etc The drive on which data are buffered can only be changed when all open Chart files have been saved Close any open Chart file containing data and choose Edit gt Preferences gt Data Buffering to choose where data will be buffered The Data Buffering dialog appears Figure 2 18 Buffer files can be stored on any local fixed disk removable media or storage media on a network cannot be used Select a storage disk from the drop down list The amount of free space available is displayed for each option when it is chosen By default data are stored on the disk with the most free space When Chart starts recording it creates a Chapter 2 Introduction to Chart 41 Figure 2 18 The Data Buffering dialog Data Buffering Select a disk to record to from this Currently buffering to drive 7 4 drop down list Buffer data on drive WARE Ci 29305 MBytes free Available space on the chosen Regularly update disk buffer every 60 seconds d isk Warning disabling regular updates will increase performance buk can Click here to choose how data result in data loss if the computer loses power or is reset or if the Operating System crashes are buffered buffer file in the root directory of the chosen disk This temporary
268. ring page 51 options can be set independently for each channel s input You can type in appropriate channel titles page 60 and define units of measurement page 55 for each channel Display colors patterns and grids can be altered page 82 A toolbar page 34 allows common operations to be performed with a single click of the mouse Recording You can not only view data as they are sampled but also review past data while sampling in a split page 38 or single window page 92 Sampling rate and range can be changed while recording at lower sampling rates You can start and stop sampling at any time page 35 and build up a Chart file with many individual sections of data Files are usually buffered to disk page 41 and data recorded this way can survive a power failure which is especially useful for lengthy recordings Comments to mark events can be made during page 37 or after page 122 recording on all or on specific channels 22 Chart Software Saving Printing and Editing Chart recordings can be printed page 118 edited and saved to disk for later review page 23 You can save the settings of any Chart file page 114 to enable an experiment to be repeated quickly and easily without having to go through the process of setting it up again You can print a selection or save it as a file this allows for easy editing by extracting only that part of the recording you need You can append files to the end of an open
269. rocal and scales the resulting signal Since the period is the difference between valid triggering signals if triggering is lost then the period will get larger The computed signal then falls asymptotically to zero since it is based on the reciprocal of the period which gives an indication that triggering has been lost 70 Chart Software Figure 6 38 Ratemeter in action left the raw data a heartbeat right the computed input in min Figure 6 39 Period left raw data right computed input for the same waveform Period A period is the time taken to complete one cycle of a regularly recurring waveform The Period computed function is basically the Ratemeter without the reciprocal and gives information about the periodic behaviour of a waveform period period The Period function shows variations clearly id 500 1500 0 7000 500 500 eee 1000 The period is the difference between valid triggering signals so if triggering is lost then the period will get larger and will increase until the maximum period for the set range is reached Chapter 6 Data Analysis 19 Figure 6 40 Frequency left the gradual change used by Chart right if summation were coarser Frequency Frequency is how offen a given event occurs within a certain time The Frequency function measures the frequency of the waveform in hertz cycles per second up to 2000 H
270. rolling by clicking the Pause button at the top right of the data display area it looks like the pause button on a tape or CD player Click the Scroll button like the play button on a tape or CD player to start scrolling again The depressed button is the active one of the pair You can shift and stretch the vertical Amplitude axis to make the best use of the available display area Apart from being at the right rather than the left it is much the same as the Amplitude axis in the main window and the controls such as the Scale pop up menu function identically Changes made here are reflected in the Chart View Filtering The AC Coupled checkbox provides each input with a high pass filtering option Low pass signal filtering options are provided by a Low pass drop down list The Mains filter checkbox provides the option of filtering mains hum More filtering options are provided by the Digital Filter channel calculation Chapter 3 Setting Up Chart l 4 coupled Low pass CF a V Refer Digital Filter p 173 _ Mains filter V Refer Noise p 18 AC coupled Unless the AC coupled checkbox is selected the input amplifier will be DC coupled and pass both DC and AC signals When AC coupling is used a high pass filter before the first amplification stage removes any DC and low frequency components from the input The cut off frequency is 0 1 0 5 Hz depending on the e corder The AC coupled option is useful to r
271. rs from the given text string ROUND number precision Rounds the given number to the supplied number of decimal places ROUNDDOWN number numberOfDigits Rounds a number down ROUNDUP number numberOfDigits Rounds the given number up to the supplied number of decimal places ROW reference Returns the row number of the supplied reference ROWS range Returns the number of rows in a range reference SEARCH search_text text start_position Locates the position of the first character of a specified text string within another text string SECOND serial_number Returns the second that corresponds to the supplied date SIGN number Determines the sign of the specified number SIN number Returns the sine of the supplied angle SINH number Returns the hyperbolic sine of the specified number SQRT number Returns the square root of the specified number STDEV number_list Returns the standard deviation of a population based on a sample of supplied values Appendix A Data Pad Spreadsheet Functions 257 STDEVP number list Returns the standard deviation of a population based on an entire population of values SUBSTITUTE text old_text new_text instance Replaces a specified part of a text string with another text string SUM number _list Returns the sum of the supplied numbers SUMIF range criteria sum_range Returns the sum of the specified cells based on the given criteria SUMSQ num
272. rt You can paste cut or copied selections of Chart data directly into the same or another Chart document This enables the quick creation of new files containing summarized results from much larger recordings First make your selection in the Chart View by dragging along the Time axis to select the area of interest between two points on the axis Chapter 5 Working With Files 103 Data are cut or copied from all channels over this period even if some are not selected Choose from the Edit menu either Copy Chart Data to leave the original data intact or Cut Chart Data to clear the original data With the data then on the Clipboard you can choose where to paste Make the Chart View for the destination document active Data on the Clipboard can be pasted anywhere there is an active point or selection in the Chart View by choosing Paste from the Edit menu or typing Ctrl V Data are added to the right of an active point or replace a selection In either case since you have created a discontinuity in the record a new block is formed It is marked by solid vertical lines at each end or new scales if channels ranges change If there is no active point or selection in the Chart View then the Paste menu command is dimmed and cannot be chosen To add the data to the right end of the document as if the data were a newly recorded block choose Paste At End from the Edit menu or type Ctrl Shift V Copying to other Applications
273. s then the Panel will have a Stimulate button so you can start stimulation Note that even if you have chosen When recording starts in the Start controls you still get a Stimulate button in the case where you have chosen discrete stimulation This allows you to repeat a finite series of steps or pulses after the first series that was output when recording started Click the up or down arrows to increment or decrement the stimulus parameters You can also just select the text in one of the text entry boxes and type in the value you want then type Enter to make it take effect or type Tab to enter the value and select text in the next text entry box FZ Chart Software Figure 3 17 The Select e corder dialog The Stimulator Output All stimulation voltage is generated by the e corder via the output sockets on the front of the e corder giving a positive negative or differential stimulus depending on the sockets used When the positive output socket is used a positive stimulus voltage will give a positive voltage output and a negative voltage a negative one When the negative output socket is used the voltage outputs are inverted When both output sockets are used the stimulus will be the difference between the voltages at the positive and negative outputs you could generate up to a 20 volt pulse given a 10 V stimulus On e corder 821 and 1621 e corder models Output 1 is the positive output socket and Output 2 is the nega
274. s about a recording that are attached to and saved along with a Chart data or settings file To open it choose the Notebook option from the Window menu The Notebook window Figure 6 15 can be used whether or not Chart is sampling Rabbit Cardiorespiratory Notebook BHA Enter text here to describe your experimental protocol The title of the Notebook window includes the name of the Chart file that it belongs to The Notebook window can contain up to 32 000 characters including spaces You can scroll vertically through the 156 Chart Software Notebook contents using the Scroll bar or you can use the up and down arrow keys to move through the text line by line Click the Time or Date buttons at the bottom of the window to add the current time or date to your notes at the insertion point in the format set for your computer The commands Cut Copy Paste and Clear Selection can be used to edit text although you cannot paste graphics into the Notebook Saving The contents of the Notebook window are saved with the settings of a Chart data or settings file when you save that file This allows you to save information that may help explain a Chart file such as the name of the experiment experiment settings protocols macros etc The Notebook can be used as a simple template to indicate conditions and results an experimenter should write down If you append settings to an existing Chart file the Notebook text is not replace
275. s are available with two four eight or sixteen input channels First Use Ensure that the e corder is connected properly to your computer this is covered in the e corder Manual and turned on Double click the Chart desktop shortcut or choose Chart from the All Programs menu of the taskbar s Start button under eDAQ if Chart has been installed in the default location Chart Software Figure 1 1 The Chart License dialog Figure 1 2 The dialog that appears if an e corder is not detected when Chart starts up Licensing Chart The first time you run Chart you will be presented with the dialog shown in Figure 1 1 Enter your name minimum three characters organization minimum three characters and you license code located on the back cover of the case that contains the Software Installer CD Click OK to enter the license or Exit to leave Chart Chart License Name License Code 7095 47 26 xxxx Please enter your Chart license details You must enter a license before Chart will run e corder Detection There may be a short delay while the program sets up the e corder If the e corder is not properly connected or is turned off then the dialog in Figure 1 2 will appear If the dialog appears when the e corder is connected and turned on see the e corder Manual for help Some of the information from that guide on hardware start up problems is repeated in Appendix B in this manual If the dialog appears
276. s available depends on the range set for the trigger channel E The slider bar can be used to set the value in the normal way by dragging the sliding handle or clicking the slider bar area The value is displayed in the text entry box to the left of the slider bar Alternatively you can enter a value directly in the text entry box Start When External Trigger or a channel is selected in the Trigger drop down list the Start drop down list becomes active It offers the choice of At Event Post Trigger or Pre Trigger to determine how Chart reacts to the trigger event that is whether there is a period of time between the triggering event and the start of recording When At Event is selected sampling starts as soon as the trigger event occurs and the Start time controls are not displayed When Post trigger is selected sampling starts after the trigger event occurs at the time set with the Start time controls This is useful in cases of delayed response if the signals you want to record will occur some time after the trigger event When Pre trigger is selected sampling starts before the trigger event occurs This is useful to record the onset of an event before the trigger level voltage is reached Pre triggering relies on data buffered in memory so the anticipation is limited by available memory at the time sampling starts Pre triggering may result in negative values in the Time Chapter 3 Setting Up Chart 65 EL Ep g
277. s frequency as well as the 50 or 60 Hz fundamental and therefore effectively removes non sinusoidal interference such as that commonly caused by fluorescent lights The filter should not be used when e the interference changes rapidly The filter takes about 1 second to adapt to the present level If interference is present and then is OZ Chart Software Single sided Differential V Refer Channel Controls p 48 d Invert suddenly removed interference in the filtered signal will temporarily worsen e your signal contains repetitive components at frequencies close to the mains frequencies e your signal is already free from interference If the signal to noise ratio is greater than about 64 the mains filter introduces more noise than it removes e you are recording at close to maximum sampling rates The mains filter uses some of the e corder s processing power and therefore reduces the maximum rate at which you can sample The template is not fully generated until about 1 second after sampling starts and so the mains filter is not fully effective in the first second of each data block Signal Input Controls The Range pop up menu lets you select the input range or sensitivity of the input Changing the range in the Input Amplifier dialog is equivalent to changing it in the Chart View The Single sided and Differential options control a signal that is input through the differential inputs i e the
278. s from that settings file You can also apply a settings file to an existing file by appending the settings file This affects the display of existing data and the recording settings for subsequent sampling It does not affect the recording settings of or alter existing data ranges sampling rates applied units etc are all left unchanged Text File This format saves data as a standard text file able to be opened by any application that can import text such as a word processor spreadsheet or statistics package or Chart itself Each sample recorded is stored as a row of data readings for each channel separated by tabs and 114 Chart Software Figure 5 14 The Save Document As Text dialog with Channels 1 and 2 selected for saving V Refer Saving Options p 113 ending in a return character that is taking up a single line If you opt to save a Chart file as a text file the Save Document As Text dialog appears when you click Save it lets you choose how many columns of data you end up with and what is in them The controls in the dialog are the same as those in the Convert Chart Data to Text dialog See Pasting Chart Data as Text on page 104 Save Document As Text Channels Include li f2 alalslel7lel Mime Always Seconds Channel settings Comments ut oF range data Clip out of range data values Output NaN For out of range data values Reduction E Link bound to selection CIUS reg
279. s on creating configuration files with an example can be found in Appendix E Selecting Data You will often need to make a selection of data in the Chart View as a first step to further manipulation or analysis for example to zoom in on it or to transter data to the Data Pad Chart provides two approaches to making and adjusting selections directly in the Chart View and using the Set Selection dialog Making Selections Directly If you click in the Time axis a vertical line indicates the active point over all channels if you click in a channel the line and active point are confined to one channel Figure 5 3 top An active point is distinct from a selected area and marks a position rather than selecting anything It can be used for adding comments transferring information on time or value at an active point s position to the Data Pad and the like Since it is not a selection though you cannot copy the data to the Clipboard zoom in on it etc To select an area of data in one channel position the pointer and drag to highlight a rectangular area Figure 5 3 bottom Shift click to extend the selection in the channel The extent of vertical selection 98 Chart Software Figure 5 4 Selecting data in multiple channels left from the Time axis right Shift dragging in the channel you want to add affects display in the Zoom View but will not affect display in the XY View Spectrum window transfer of in
280. s selected times are still checked for decreases or changes in interval which are taken to mean block boundaries If you are importing a text file derived from another data acquisition system that does not put time values in the first column you may want to edit the text file to include an Interval data header as the first row Interval ExcelDateTime TimeFormat ChannelTitle Range 0 00 00 00 0 00 00 0025 0 00 00 005 0 00 00 0075 0 00 00 01 0 00 00 0125 0 00 00 015 0 00 00 0175 0 00 00 02 0 00 00 0225 3 7126533958333336e 04 23 08 2001 12 48 54 0 0025 s StartOfBlock Pulse PCG 10 V 10 V 13 469 3 484 16 453 6 766 20 391 8 891 19 016 10 656 13 391 11 344 6 766 11 719 3 172 12 469 4 297 12 422 9 359 14 047 15 453 13 547 Electrode 50 mV 0 01650 0 01988 0 02338 0 02388 0 02019 0 01300 0 00800 0 00181 0 01319 0 03831 2 Comment for Channel 2 Comment for all channels 250 Chart Software ExcelDateTime and TimeFormat The ExcelDateTime keyword and value indicate the date and time in coded form of the original recording TimeFormat indicates in what form the time was saved Chart uses the values to reconstruct time information from the loaded file and match the original Chart file exactly These keywords have no use in files from sources other than Chart ChannelTitle The ChannelTitle data header simply records the channel title for each channel Range The Range dat
281. s the specified number of characters from a text string beginning with the specified starting position MINUTE serial_number Returns the minute that corresponds to the supplied date MOD number divisor Returns the remainder after dividing a number by a specified divisor MONTH serial_number Returns the month that corresponds to the supplied date N value Tests the supplied value and returns the value if it is a number NOT logical Returns a logical value that is the opposite of its value NOW Returns the current date and time as a serial number ODD number Rounds the specified number up to the nearest odd integer 256 Chart Software OFFSET reference rows columns height width Returns the contents of a range that is offset from a starting point in the spreadsheet OR logical_list Returns True if at least one of a series of logical arguments is true PI Returns the value of the constant pi PRODUCT number list Multiplies a list of numbers and returns the result PROPER text Returns the specified string in proper case format RAND Returns a number selected randomly from a uniform distribution greater than or equal to O and less than 1 REPLACE orig_text start_position num_chars repl_text Replaces part of a text string with another text string REPT text number Repeats a text string the specified number of times RIGHT text num_chars Returns the rightmost characte
282. sampling rate set in Chart this means that if you choose a sampling rate of 2000 s or slower computations use raw data sampled at 2000 s and if you choose a sampling rate above 2000 s computations use raw data sampled at the set rate The sampling rate you can set is limited by the number and type of computed inputs chosen since different functions use different amounts of processing power as well as the computer and the connection Signal Displays The raw and computed data are displayed so that you can see the effect of changing the settings No data are actually recorded when setting up computed input although stimuli can be generated while the dialog box is open so that Stimulator output waveforms can be observed The current signal value is displayed at the top left of each display area Slowly changing waveforms will be represented quite accurately whereas quickly changing signals will be displayed as a solid dark area showing only the envelope shape of the signal formed Chapter 6 Data Analysis 185 Raw Data Input fi by the minimum and maximum recorded values You can shift and stretch the vertical Amplitude axis of each signal display to make the best use of the available display areas Apart from being at the right each display s Amplitude axis is the same as the Amplitude axis in the Chart View and the controls function identically Raw Data Controls By default Chart channels record the raw d
283. set using the Channel Settings dialog Note that the resolution of the recorded data is independent of the resolution of the display Unless an input is turned off data will be logged in it at full fidelity during recording even if the channel separators have been adjusted so that the channel is very thin and its data display area is not visible on the screen The Split Bar You can split the data display area of the Chart View vertically into two sections or panes to compare different sections of recorded data or to compare recorded data with newly sampled data When 78 Chart Software Figure 4 2 Splitting the data display area drag the Split bar to the desired position and release the mouse button recording you can choose to record or review in either pane use the Scroll Review button to toggle between recording and reviewing When reviewing you can perform most normal operations in the pane make selections use the Zoom View Spectrum window and XY View add and remove comments add data to the Data Pad copy data to other files change data compression etc To split the window position the pointer on the Split bar anywhere along its height so that it changes into the split pointer The vertical Split bar is at the left side of the data display area Drag the Split bar to the desired position so that the two panes of the window are the sizes you want them a line appears to indicate where it will go
284. sh the sum to update as you add data to the Data Pad you need to leave a blank cell below the last value in the column and then include that cell when you specify the cell range over which you are summing as shown in Figure 6 10 FingerPulse Data Pad yA 40 points from t 2 33 37 FingerPulse Data Pad yA 40 points from t 2 33 37 E Channel 1 Integral FingerPulse Data Pad Channel 1 Channel 1 Channel 1 Integral Channel 1 Integral 25 202 22 0046 26 4162 25 6646 1r ardd 22 0036 19 6647 22 0046 5 5412 26 4162 5 9436 25 6646 a Fas 1r ardd 4 TTO 22 0036 5 7009 19 6647 4 4245 22 0846 5 5212 26 4162 5 9436 25 6646 5 7745 17 3744 4 778 22 8036 5 7009 37 7181875 32 142344 2 Sum calculated on pressing the Enter key 1 Blank cell included in sum range 3 New row of data added to Data Pad is included in sum 146 Chart Software You can set up a column of the Data Pad with a custom formula using spreadsheet functions provided that column is not already set up with a function from the Data Pad Column Setup dialog To do this make sure the Cell button is clicked choose the Unfix Top Row command from the Data Pad drop down list and then enter the formula into the top cell of the column You can add a custom column heading by holding down the Control key and double clicking a column header This opens a dialog which allows you to type in a heading Th
285. sing Multiple Add to Data Pad or Timed Add to Data Pad the added data also appear in the destination document Rows that overflow the original Data Pad selection do not get pasted into the destination document Opening Text Files When you open a Chart file from the Open dialog you can choose whether to open a data file settings file or text file If you have certain Chart extensions installed you may be able to open other types of files as well Chart for Windows can reimport data saved as text from Chart or Scope Windows or Macintosh versions or other data acquisition systems Data can be manipulated before being imported or even created to test a theory in a spreadsheet or data analysis program When opening text files Chart expects each recorded sample to be stored as a row of numeric data readings one for each channel separated by tabs and ending in a return character or line feed character or both that is taking up a single line Figure 5 9 Blank lines or lines starting with the character are ignored If time values are included they should be the first entry in the row A decrease in time values or a change in the time interval is taken to signify the start of a new block Missing data points or untranslatable data points are represented by NaNs Not a numbers When reading a text file saved from Chart or Scope Chart loads only the data and possibly the sampling rate range units conversion Chapte
286. sing Replace Row with Current Values from the Data Pad pop up menu Recalculate To recalculate the row data select one or more rows and choose Recalculate from the Data Pad pop up menu Alternatively to update all rows in the Data Pad at the same time choose Recalculate All from the pop up menu The row data is updated and will reflect any changes in the channel data perhaps due to having applied units conversion or a channel calculation or the data pad column setup Deleting part or all of the data associated with a row breaks the link and prevents reselection and recalculation Deleting data in the document not associated with any link does not affect the correct reselection of data Printing When the Data Pad window is active then the print option in the File menu changes to Print Data Pad and if the command is selected the contents of this window are printed rather than those of the Chart View The Data Pad will print across two or more pages if it is wide enough but individual columns will remain intact Saving as Text or Excel You can save the contents of the Data Pad as a text file or as an Excel tile without saving the Chart file as well To do this choose Save As from the File menu with any window active and select Data Pad Only as Text File or Data Pad Only as Excel File from the Save as type drop down list Save as type Chart Data File edcht v Chart Data File edcht Chart Text File
287. st allows you to chose whether cycle detection triggers on the maximum or the minimum point of the detected cycle Preview Area The Preview area displays the selected source data the effect of any applied preprocessing as well as markers to indicate detected cycles It does not show the results of cyclic measurements results are displayed in the Chart View The Preview area can display two Amplitude axes as well as compression controls similar to those of the Chart View It also has controls to allow you to review previously recorded data or to monitor the current signal at the input Chapter 6 Data Analysis 167 e When the Review button Figure 6 19 is depressed the display area shows the data recorded in the selected channel up to the moment when the Cyclic Measurements dialog was opened e When the Monitor button is clicked the display area shows new data sampled from the currently selected input Clicking the Review button dumps the new data and displays the recorded data in the channel The Pause button allows you to review the sampled data The Sample button is inactive when Chart is sampling Measurement The Measurement drop down list gives the cyclic measurements that can be calculated from detected cycles There are rate functions Rate Period and Frequency amplitude functions Mean Minimum Maximum Height and 1 3 Max 2 3 Min calculus functions Integral Minimum Derivative and Maximum Derivative and V
288. t Axes 200 1 500 1 The horizontal Time axis above the Scroll bar along the bottom of the ik 1 m Chart View records the time from the start of sampling or the absolute time in various forms depending on the time format which can be set using the Display Settings dialog For each channel the vertical Amplitude axis on the left of the window V Refer indicates the amplitude of the recorded waveform Note that the axis The Amplitude Axis p 79 area remains blank until some data are actually recorded The scale for each channel is initially set by the Range pop up menu on the right side Chapter 2 Introduction to Chart J V Refer Units Conversion p 55 V Refer Channel Controls p 48 1 535 Differential of Channel 1 Range 10W Using input 1 Rate 400 fs Hidden Recorded Data Range 10W Using input 2 Rate 400 fs Block 3 25 10 2003 11 34 45 201 of the window but can be stretched or dragged using the pointer Display options can be chosen from the Scale pop up menu this cannot be used if the channel has no visible data The units of the active channel are shown in the axis Units are volts by default but may be changed to mmHg Q kPa or any other unit that you need by using units conversion Scaling Buttons The Scaling buttons are on the left side of each channel s Amplitude axis Click the button to enlarge or the button to reduce the vertical scale halving or doubling what is shown each
289. t Software 265 Cyclic Measurements command 165 Derivative command 170 Digital Filter command 174 Input Amplifier command 51 Integral command 177 Legacy submenu 49 No Calculation command 158 Shift command 180 Smoothing command 181 Turn Input Off command 49 Turn Input On command 49 Units Conversion command 55 Channel miniwindow 92 channel separators 33 78 Channel Settings dialog 60 87 channel settings information 32 Channel Settings command 59 86 channel titles 87 Chart Application window 28 Chart documents 24 Chart extensions 158 218 Chart files 24 Chart License setup dialog 11 Chart startup options 201 252 Chart View 30 34 printing 119 splitting 78 79 Chart View command 78 Chart window See Chart View Check for Updates command 12 Clear Channel command 102 Clear Selection command 102 Clipboard 103 Close All command 94 Close command 27 closing a Chart file 27 color 61 87 Color drop down list 86 87 command line options 252 Commands menu 223 Add Comment command 123 Add to Data Pad command 138 Auto Scale command 82 Find Next command 135 Find command 132 Go to End of Data command 30 Go to Start of Data command 30 Set Marker command 131 comments 122 127 adding after recording 123 124 adding while recording 37 122 123 boxes 84 123 deleting 125 editing 125 finding 126 134 identifying data points 126 132 including in text file 105 lines 84 numbering 11
290. t do have entries The section name folder is optional and is followed with a key line whose value is text that will be shown in the information area in the Experiments Gallery dialog This text is usually used to give a general description of a folder If this section is omitted the info area is not shown Chart Software 261 Key Lines A key line contains a key name followed by an equals sign and a key value Spaces around the key value are ignored Long values may be continued onto the following line by using a solidus character as the last character on a line The solidus is not part of the key value text The following keys may be used within a filename section e Text This key provides the text to be shown as additional description text for the file e Flags Various options used to control some of the behavior and appearance of the entry for a file Available flags are e Bold Show the label filename and descriptive text in bold face e Default Make this the file selected in the file list whenever the folder containing it is selected e MacOnly Only show this entry on a Macintosh system e WinOnly Only show this entry on a Windows system e Hide The entry is not shown in the file list e ShowErrors Display the Errors button in the Experiments Gallery dialog when there are problems with the files or folders referenced Comment Lines A comment line starts with a semicolon Comment lines
291. t experiments and make them easily accessible to students If you are a researcher you will also find it useful for organizing and getting easy access to your recordings Using the Experiments Gallery Before you can use the Experiments Gallery it must have been created and files or folders must have been added This may have already been done in your version of Chart but if not see Managing the Experiments Gallery p 97 Once the Experiments Gallery is in place the Experiments Gallery dialog will be displayed when you choose Experiments Gallery from the File menu If you select the Show Experiments Gallery at startup checkbox at the bottom of the dialog it will also be displayed when e You start Chart without a document for example when you double click the Chart desktop shortcut e You close the last open Chart document The left hand pane of the dialog contains a folder hierarchy of the Experiments Gallery contents It is similar to the Microsoft Windows Explorer and is navigated in the same way clicking on the plus icons to expand branches of the folder structure for example In the right hand pane are shown the files in the folder selected in the left hand pane The selected file is indicated by a surrounding rectangle and can be opened by clicking the Open button Alternatively you can double click tiles to open them Depending on how the Experiments Gallery has been set up there may be an information area above th
292. ta points minus the value on a baseline multiplied by the sample interval gt y ypaseline At The baseline is a straight line joining the first and last points in the selection Block Information Block Range returns the range used when recording for the block containing the active point or selection Sample Interval returns the time between samples for the block containing the active point or selection Sampling Rate returns the sampling rate used when recording the block containing the active point or selection Block Number returns the block number for the block containing the active point or selection Block Duration returns the total time of the block containing the active point or selection Samples in Block returns the total number of samples in the block containing the active point Block Start Time returns the time of day at the start of the block containing the active point or selection Block Start Date returns the date at the start of block containing the active point or selection If a selection straddles two or more blocks however then it will be noted as discontinuous Cyclic Measurements Cyclic Measurements parameters are for analyzing periodic waveforms The calculation of each parameter is based on waveform cycles When a Cyclic Measurements parameter is selected in the Data Pad Column Setup dialog an Options button appears Clicking this button opens the Data Pad mode of the Cyclic Measurements dialog which allows
293. ta to appear and select Paste Special from the Edit menu In the Paste Special dialog that opens select the Paste link option Select the format with which to insert the contents of the clipboard Data Pad data is text so the Picture option is not available and the Convert Chart Data to Text dialog does not appear Click OK You can pre link Data Pad rows to the destination document so that data added to the Data Pad for example while recording is also added to the destination document Ike In Chart select the Data Pad insertion row just under the last added row of data and sufficient additional rows for the data that will be added The selection can include title rows Selecting entire 108 Chart Software Vv Refer Opening a Chart File p 24 Chart Extensions p 218 rows in the Data Pad to paste into Word and Excel can avoid the risk of overflow Copy the selection 2 In the destination document position the cursor where you want the data to appear and select Paste Special from the Edit menu 3 In the Paste Special dialog that opens select the Paste link option Select the format with which to insert the contents of the clipboard Data Pad data is text so the Picture option is not available and the Convert Chart Data to Text dialog does not appear Click OK Any title rows are pasted and rows to the number in the selection are highlighted 4 If you now add data rows to the Data Pad for example u
294. te the amount of disk space available and how much the file has used 28 Chart Software Figure 2 6 The Chart Application window with some document windows Document Windows Each Chart tile may have associated with it a number of document windows The Chart View is where data is recorded and other document windows such as the Zoom View provide alternate views of the data Document windows are contained within the Chart Application window and can never escape or spill over onto the desktop the Chart Application window acts like a desktop to them Figure 2 6 Within these confines they can be moved resized closed maximized restored or shrunk to a minimized state 28 Chart File Edit Setup Commands Macro Window Help Chart oh amp Eggja Ft Kd H 2j gt Start Application window Waveforms Chart View Idle O Channel a i Comment Add Chan View ij 200 my fi Toad H BEE Muscle BEE sis ocumen 344 1 MB windows Document windows can be maximized thus effectively combining with the Chart Application window to act as one window by clicking their maximize buttons In this case document window titles are shown in the Chart Application window Title bar in brackets after the application name Figure 2 8 When Chart or a Chart file is opened the Chart Application window appears by default with the Chart View filling the space available For the most part this manual assumes you are dealing
295. tems can potentially be obtained by stopping and saving then continuing or by appending files Although you can record very large files in Chart to ensure optimum performance and manageability it is best to keep your files smaller than about 10 MB 5 000 000 data points where possible this shouldn t be a problem for most users It takes a long time to deal with the data in a gigabyte sized file for instance saving could take many minutes during which recording might not take place In practice you need to have as much space as a file takes up itself in order to save the file so to save a 10 MB Chart file you would need 20 MB of free space when you start recording This is for a new file so if space is constrained and you are recording to a very large existing tile you may not be able to save the resulting file in one piece When Chart starts up the amount of space available for recording is shown in a memory indicator at the bottom right of the Chart Application window The memory indicator shows the amount of free space in megabytes As you record a progress indicator shows how much of this available space has been used when it reaches the right edge indicating that the file is at the maximum size that can be saved Chart stops sampling and puts up an alert to tell you what has happened When a file is saved the amount of space available for recording is recalculated and the memory indicator is reset ga p Data Buffe
296. tep mode you can specify how many steps from 1 to 2000 you want in your stepped waveform Discrete Waveforms If the lower of the two radio buttons at the top left of the window is selected Set Number of Pulses for Pulse Once Only for Step then the stimulator will produce the number of pulses you set or for Step mode a single stimulus If you choose Pulse from the Stimulator mode drop down list you can specify the number of pulses to be produced by the stimulator from 1 to 2000 using the Number of pulses control If you choose Step mode the control is labeled Number of steps and you can specify how many steps from 1 to 2000 you want in your stepped waveform Chapter 3 Setting Up Chart 69 Figure 3 15 The Marker channel drop down list Start When recording starts O Manually Delay oo E ms BPM Hz Range Marker Channel It can be useful to mark a stimulus pulse so that you can measure from that point To mark the point at which a stimulus starts on a channel select that channel from the Marker channel drop down list A small spike will then be marked in the selected channel overlaid on any data there If you choose Off in the drop down list no marks are recorded Marker channel Start Mode Click When recording starts to start the stimulator when the Start button is clicked If the stimulus waveform is continuous the Stimulator panel controls will then include Off and On b
297. th Files 95 The Experiments Gallery 96 Using the Experiments Gallery 96 Managing the Experiments Gallery 97 Selecting Data 98 Making Selections Directly 98 Using Set Selection 100 Deleting Data 102 Transferring Data 103 The Clipboard 103 Copy Cut and Paste within Chart 103 Copying to other Applications 104 Opening Text Files 109 Saving Options 113 Saving a Selection 115 Appending Files 116 Printing 118 Page Setup 118 Print Preview 118 The Print Command 119 Comments 122 Backing Up Files 127 6 Data Analysis 129 Measuring from the Waveform 130 Using the Marker 130 Finding Data 132 Search Criteria 133 Selection Criteria 134 Repeatedly Finding Data 135 The Data Pad 135 Adding Data to the Data Pad 137 Setting Up the Columns 139 Source Data for Rows 144 Printing 145 Saving as Text or Excel 145 Spreadsheet Functions 146 The XY View 147 The Spectrum Window 151 Spectrum Settings 152 The Notebook Window 156 Channel Calculations 158 Arithmetic 159 Cyclic Measurements 165 Derivative 170 Digital Filter 173 Integral 177 Shift 180 Smoothing 181 Computed Input 184 Sampling Rates 185 Signal Displays 185 Raw Data Controls 186 Computed Input Controls 189 Computed Input Functions 190 Chart Software 7 Customizing amp Automating 199 Preferences 200 Default Settings 200 License Manager 201 e corder Startup 201 Menus 202 Controls 204 Cursor 205 External Trigger Options 205 Special Access 205 Macros
298. th a minimum of one sample interval and choose whether the command applies to the whole tile the block currently containing the active point or the current selection in the Chart View Repeat Select Every Selection period o Minutes Seconds Step through Whole file Block containing selection Current selection Allow partial selections Allows a shorter Final selection if the duration is mot an exact multiple of the selection period You could for example transfer data to the Data Pad for every ten second period of the recording The checkbox lets you decide macro behaviour if the length of the file block or selected data is not an exact multiple of the chosen selection period If it is deselected then any time left over less than the selection period is ignored If it is selected then the last selection will be a shorter time making up the balance for example if the block were 45 seconds long and the selection period 10 seconds the last selection would be the remaining tive seconds Chapter 7 Customizing amp Automating 215 Figure 7 18 The Repeat Select Every macro command in action For instance Figure 7 18 shows a macro selecting a period of data 0 1 seconds sequentially through a Chart file each selection of data is dealt with before moving on to the next one When this macro command plays it will scroll through the Chart file and highlight each new selection Peri
299. the Chart View Again comments are printed out as a numbered list with the numbers boxed as they are in the Chart and Comments windows Only those comments chosen for display using the Channel Number buttons in the Comments window will print If the Show Times checkbox is deselected then times will not be printed This helps if you have long comments since comment text longer than one line will not be printed the text is truncated Backing Up Files It is always good practice to back up computer files Computers are reasonably reliable but file corruption disk failures and accidental deletion of data can still occur You can get data backup software to back up your Chart files automatically or you can set up a backup schedule yourself Off site and Internet based backup services are also available It helps if things are well organized and your files and folders are sensibly named so that you can find backups easily Although Chart compresses data you may save some space by archiving data files Simply copying files to another disk is enough having copies on the same disk doesn t help if the disk fails The most reliable backup media are recordable CDs magneto optical disks or hard disks including servers especially if they also have tape backup Floppy disks are best treated as temporary media only Whatever you do you should test your backup procedures Try backing up and retrieving files to make sure things work
300. the dialog show the menus and menu commands that can be modified The lefthand scrolling list Menus shows the menus available including those added by macros and extensions The righthand scrolling list Items shows the menu commands and items in the menu selected in the Menus list Click any menu in the list to select it and see its contents in the Items list 202 Chart Software Figure 7 4 The Menus dialog Menus af ty Experiments Gallery ff Exit ee ea r wf Setup Ctrl M f Commands wf ty Open Ctrl eo Macro wf ty Append Window f Help wf i Close wf ty Save Ctrl s Show on toolbar By default the menus and menu items have a tick to their left and all menu commands will have an open padlock beside them as well indicating that everything is visible and unlocked Note that dividing lines between groups of commands have no padlocks beside them they are not commands and therefore it makes no sense to lock or unlock them Clicking a tick will change it to a cross and hide the item beside it Clicking the tick beside the menu title in the Menus list will hide the menu it will not appear in the menu bar when you return to the Chart View and any keyboard shortcuts in it will not work Clicking the tick beside a menu command or a dividing line in the Items list hides it it will not appear in the menu and neither will any keyboard shortcut work Clicking a cross will change it to a
301. the file and subsequently appended to it say will appear with a negative time relative to the start of the record Very large values to the right of the Time axis reflect a large lag between the time the record was created and the latest recording Appendix A Troubleshooting 231 e f the values are a problem simply change the time mode display to show time from the start of each block the default setting Commands seem to have no effect or a strange one Commands do not work in all circumstances If you have no selection or active point in the Chart View for instance you cannot use commands to do with selections or active points such as adding data to the Data Pad or printing a selection you cannot print active points e Make sure you have a selection or active point in the Chart View as needed or otherwise have things appropriately set up Macro recording might have been turned on so that you record what you are doing rather than actually doing it If so then Stop Recording will be the first menu command in the Macro menu and the Status bar at the bottom of the Chart Application window will read Recording Macro e Choose Stop Recording from the Macro menu and discard the macro since it will likely be of little use Keyboard shortcuts don t work or do strange things Menu commands may have been deleted or keyboard shortcuts reassigned to other menu commands or macros e Look at the menus and com
302. the s or ms radio button to set the range for the Step width control to seconds or milliseconds respectively The Step width controls set the exact duration for the step width within these ranges from 1 sto 5 s for seconds and 50 ps to 1 s for milliseconds The scale on the Step width control is logarithmic The Pulse duration control is set by default to the same value as the Step width control If you leave the control set as it is a stepped ramp waveform as shown in Figure 3 14 center will be generated If you change the control to be less than the step width it cannot be set to be greater then a ramped pulse waveform as shown in Figure 3 14 right will be generated Output Range Amplitude and Baseline For Pulse mode the Output range drop down list lets you select the range for the Amplitude and Baseline controls The available ranges are 200 mV 500 mV 1 V 2 V 5 V and 10 V The Amplitude control is used to set the exact amplitude voltage either positive or negative within these ranges The Baseline control sets the exact baseline voltage within the range the pulse waveform just adds the positive or negative pulse to the baseline voltage You can use the baseline voltage with no defined pulse that is with Off selected in the Stimulator mode drop down list to generate a continuous voltage from the e corder outputs Output Range End Level and Start Level For Step mode the Output range drop down list lets you select the rang
303. the time between samples set by the user and displays it during the next sampling interval remember that the e corder always samples data for computed input at 2000 samples per second or more even if the sampling rate set by the user for recording to disk is much less For example if you set a sampling rate of one sample per second in Chart then the maximum value of the samples in the previous second would be shown each second in the display Information is not required about cycles or periods in the incoming data so the triggering controls don t appear The Envelope Minimum function works similarly except that the minimum value over a time is found and displayed during the next time period Envelope Maximum and Envelope Minimum are useful if the specifics of the signal are of no interest but the maxima or minima are important 194 Chart Software Figure 6 43 Envelope maximum note that the raw sampled data shown as open circles could be quite misleading in this case Figure 6 44 Differential the derivative of a triangular wave left is simply a square wave right Maximum trom time between previous e corder samples Ie sample times Time between samples P P since they let you record at a much lower sampling rate than would otherwise be the case resulting in smaller files As you can see from Figure 6 43 you would need to record at a far higher rate to get an accurate depiction of the waveform but
304. tings that were used to record that block on that channel Data Display Area Recorded data are shown in the area in the Chart View bounded by the channel control area on the right and the Amplitude axes on the left see Figure 2 7 The data for each channel are bounded above and below by horizontal bars These bars or channel separators can be dragged up or down to vary the size of the channel display areas double click them to restore their original positions Split Bar The vertical Split bar at the left side of the data display area can be dragged to the right to split the data display area into two parts each with its own scroll bar and Compression buttons so that you can compare different sections of recorded data or compare data already recorded with new data as they are sampled The Marker IE The Marker can be found in a box at the bottom left of the Chart View f It can be dragged onto the data display area to set a particular data point on a waveform as a zero reference point so that measurements can be made relative to that point Double click it or click its box to send it back home Start Button To start sampling click the Start button at the bottom right of the Chart be Start View or the equivalent button in the toolbar The button label then changes to Stop click it to stop sampling There may be a short delay while sampling starts or stops Chapter 2 Introduction to Chart Jo
305. tion 195 Digital Filter calculation details 242 244 Digital Filter channel calculation 173 177 Digital Filter dialog 174 Digital Filter command 174 digital filters 233 digital read outs 9 1 92 digital voltmeter 91 digitization 16 17 discontinuity 35 84 90 102 104 143 display and expectations 19 20 display offset 54 display settings 20 82 86 Display Settings dialog 83 Display Settings command 82 distributor contact information 229 divisions 46 document settings 200 Document windows 29 DVM 91 92 DVM miniwindow 91 DVM submenu 91 E e corder system 10 eDAQ contacts ii 229 Edit menu 222 Clear Channel command 102 Clear Selection command 102 Copy command 99 104 106 Cut command 99 104 Default Settings command 200 Paste At End command 104 Paste command 104 Preferences command 200 Redo command 102 Select All command 99 Undo command 102 emergency access 205 206 End Repeat command 217 Envelope Maximum computed input function 194 Envelope Minimum computed input function 194 Excel time format 108 Exit command 27 exiting Chart 12 27 expected waveform shape 19 Experiments Gallery 25 27 96 98 configuration files 261 263 Experiments Gallery command 96 extensions 114 158 218 External Trigger Options command 205 F Fast Fourier Transform 151 153 237 241 fast tracking 188 FFT 151 153 237 241 File Append directory dialog 117 File menu 2
306. tion shows which is active only one can be at any time Calculations apply to the entire length of the channel and operate on the displayed data of the input source Arithmetic can also operate on underlying recorded data You can turn off a channel calculation without losing the values you enter in its dialog You can easily set up many calculations at once or check all channels at once to see if any calculations are applied by using the Calculation column of the Channel Settings dialog Common to most channel calculation dialogs is a Source drop down list which lets you choose either the channel input or the waveform in another Chart channel as the source to be processed You are able for example to use one channel to display the source signal and another to display the calculation so as to compare the two To display only the calculated signal you would choose the input for the channel concerned Hidden Data If a channel contains recorded data and has a channel calculation applied the displayed data will be the calculated data The recorded data still remain underneath and can be seen simply by turning the calculation off Channel calculations normally work on the displayed data in a channel so you can use them in sequence For instance you could 158 Chart Software Figure 6 17 The Arithmetic dialog click OK to show the function in the display channel in the Chart View Expression text entry box C
307. tive one Using Multiple e corders Chart can be set up to record from more than one e corder This is useful if you wish to run a number of independent experiments using separate e corders but sharing the same computer or if you do not have enough channels on one e corder to record all the parameters you want in a single experiment For information on connecting multiple devices to your computer using USB please consult the e corder Manual on the Installer CD Recording from multiple e corders is done by using a single version of Chart with multiple documents open each recording data from one e corder When you start Chart with multiple e corders connected a dialog appears asking you which e corder you want to use The list indicates the model of e corder and it s serial number Choose which e corder you wish to use and click OK Select e corder Select the wou Wish to work with e corder 201 Serial No pl6m026 connected via USB e corder 1621 Serial Mo t420 0004 connected via USB Chapter 3 Setting Up Chart 73 Figure 3 18 A document Title bar showing which e corder is selected and the Select e corder dialog displayed when a document is open V Refer Trigger p 63 The Chart document that opens will show the selected e corder in its Title bar Figure 3 18 You can change the e corder a document is using by choosing Select e corder from the Setup menu this command only appears when multiple
308. tons The compression indicated in the Compression buttons indicates the samples per pixel at 1 1 each pixel represents one sample The size of the divisions may be altered slightly to 18 24 or 25 pixels to enable the unit divisions on the Time axis to 46 Chart Software correspond to round numbers This is most likely to occur at slow sampling rates and high horizontal compressions If there are 20 samples per division then at 20 1 each pixel represents 20 samples and there are 400 samples per division When you show time from the start of the day or the start of file the position of the first unit division in a block will not necessarily be on the block boundary but will be adjusted to fall at an exact time division second or whatever as measured from your computer clock Maximum Sampling Rates The Rate pop up menu is used to select the continuous sampling rate when recording is started On ecorder 201 401 205 and 405 units the maximum speeds are e 200 000 samples per second on a single channel e 100 000 samples per second on two channels or e 40 000 samples per second on 3 or 4 channels With e corder 821 and 1621 units the maximum speeds are e 200 000 samples per second on one or two channels e 100 000 samples per second on 3 or 4 channels e 40 000 samples per second on 5 10 channels and e 20 000 samples per second on 11 16 channels Maximum sampling rates may also be limited by the speed of the computer W
309. tting and adding the last number shown for the count 192 Chart Software Figure 6 41 Cyclic Mean summed area dark shading for different thresholds light shading Cyclic Mean A cyclic mean is the average amplitude of a waveform over a cycle Variations indicate some form of asymmetry in the waveform The Cyclic Mean function sums the values of the data points between two successive threshold transitions and divides by the number of points summed This calculation could be used for example to determine the mean displacement of object whose motion has both oscillating and linear components which is being measured with string potentiometer The position of the threshold control determines where the summation starts and ends but because the input is a cyclic wave the result should not depend on this Only when the waveform has some other periodic signal superimposed on it does the actual threshold affect accuracy of calculation The results you get from the cyclic mean are the same as if you selected an exact period of the raw data integrated that selection and divided the integral by the period Note that in Figure 6 41 summing starts and ends at different times when the threshold is in different places but the results are the same It would be much better in this case to leave the threshold in the center of the waveform because it will still work even if the amplitude of the signal changes slightly In both parts o
310. uencies of up to 100 Hz you could sample at 400 samples per second and filter out any higher frequencies using a 200 Hz filter If higher frequencies are left unfiltered then they could possibly be aliased resulting in the false appearance of lower frequencies Original signal high and low frequencies High pass Low pass filter filter Filtered signals Filtering can change the signal to some extent its use must be balanced against the distortions it can remove such as noise baseline drift and aliasing If the filter settings overlap the bandwidth of a signal then the signal will have components removed If you were interested in a waveform with components down to 5 Hz and used a 20 Hz high pass filter filtering out O to 20 Hz signals then vital information would be lost from the signal Digitization When analog data such as voltage amplitude is converted to digital form for use by a computer it must conform to a fixed number of values for instance a digital thermometer might only measure temperature to the nearest degree Any analog values between these values are rounded up or down The approximation is usually very good since the Chart Software Figure 1 8 A signal with various low pass filter settings some filtering cleans up noise but too much unacceptably distorts the high frequency spikes Unfiltered Noise reduced Overfiltered number of v
311. ulse duration and then falls or rises to the baseline voltage again Figure 3 14 left Step This setting can generate two types of waveform e A stepped ramp Figure 3 14 center that starts at a baseline voltage is raised or lowered to the set amplitude in a series of steps and then falls or rises to the baseline voltage again e A variation on the stepped waveform can be made by setting the duration of the voltage at each level to less than the step width resulting in ramped pulses Figure 3 14 right 68 Chart Software Figure 3 14 Types of stimulus waveform Amplitude 1 1 1 1 I Output Continuously O Set number of pulses Output Repetitive Once only Number of Pulses E UE l alal Pulse mode Step mode Ramped pulses Step mode Stepped ramp Setting the Controls The slider bars for various stimulation parameters can be used to set the value in the normal way by dragging the sliding handle The value is displayed in the text entry box above the slider bar You can also change the value by clicking the up and down arrows at the right of the text entry box Ctrl click to change the value in larger increments or by entering a value directly Continuous Waveforms By default the stimulator gives a continuous stimulus waveform and the top radio button at the top left of the window will be selected Continuously for Pulse mode Repetitive for Step mode If you choose S
312. uter the faster your computer the faster it can handle data from the e corder and hence the more time it can give to another application How slowly your other applications run while background recording is going on or whether or not they interrupt recording depends on the sampling rate as well as the speed of the computer and available memory Chart does have a memory buffer set aside so it should be able to record for a short time even when another application is using most available resources but if you are using several greedy or CPU intensive applications and haven t got that much RAM it is possible you could lose data at fast sampling rates If the computer cannot keep up then Chart will just stop sampling If this occurs avoid using those applications when recording critical data At higher sampling rates it may be best if Chart is the only application running Duration of Recording How long you can record for depends primarily on the free space on the hard disk to which you are recording Each sample takes at most two bytes of storage so recording on one channel at 200 000 samples per second for example would use 1 x 200 000 x 2 400 000 bytes 400 K of memory per second or 12 megabytes per minute Chart has some application limits as well The maximum file sizes that can be recorded in one continuous session is about 1 0 GB under 40 Chart Software Windows 2000 or XP File sizes of up to 2 GB under all sys
313. uter requirements There is also a basic introduction to data acquisition for those new to the area Chart Software Vv Refer When using the PDF version of this manual on line cross references are shown in blue and clicking on them will transport you to the reference Learning to Use Chart Where to Start To install Chart for Windows and to use it you should be familiar with the Windows environment If you do not know how to use the mouse and keyboard choose commands from the menus copy or rename tiles etc please consult the guide that came with your computer The software is designed to be easy to use but familiarity with the operating system will make learning it a lot easier If you have previously used Windows applications you should find that menus dialogs and controls all work as you might expect If you have used earlier versions of Chart you should find that this version has much in common although it has many improvements You should start by reading the e corder Manual look for the pdf file installed on you hard disk to be sure that you know how to connect your e corder to your computer properly and how to use your e corder safely and effectively Then continue with this chapter How to Use this Manual If you are in a hurry read the rest of this chapter and the overview of Chart in the next chapter Start recording data and refer to this manual when you encounter problems or unexpected results o
314. utomatically capitalized invalid shortcuts will be rejected If you choose a keyboard shortcut already in use an alert box warns you You have to remove the shortcut from a menu command before reassigning it Appendix A lists Chart s keyboard shortcuts The Steps and Size indicators tell you the number of steps recorded useful if you can t remember if you recorded all the steps of a long macro and the memory used by the macro which depends on the complexity of the procedure Click Discard to discard the macro you have just recorded Click Cancel to leave the dialog and record more steps in the macro Click OK to add the macro to the bottom of the selected menu the button is only active and undimmed when the macro has been named and a menu has been chosen Until you save the file the macro exists only in memory and is not permanently stored so it is a good idea to save the file each time you create a macro Macros are document specific 208 Chart Software Figure 7 10 The Playing Macro dialog Figure 7 11 The Delete Macro dialog Playing a Macro Once assigned a name and location a macro acts much as if it were a menu command To use one select it from its menu or type its keyboard shortcut While a macro plays the Playing Macro dialog appears and no other functions can be performed within Chart If a macro is playing you can click the Stop button in the dialog or press the Esc key to stop it at its current
315. utton buttons Rabbit Cardicrespiratory Spectrum SINC GREENE alas 1 1024 FFTs padded points 432 FFT information Art BP 5 664 Hz 51 904 mmHg q Te E S E E a a a Frequency and amplitude readings 5 664 Hz 0 0639 mieg Scale popup menu Waveform Pointer Cursor To display spectra select the area of interest in the Chart View and choose the Spectrum command from the Window menu The Spectrum window appears Only the horizontal extent of the selection affects the computation so spectra can be computed for all channels that contain data over the time of the selection even if some channels are not selected If a selection is made over two or more blocks spectra will only be calculated for the data in the left most block If the calculation takes more than a second or so a dialog appears in which you can click Cancel to stop the calculation if you wish Chapter 6 Data Analysis 1d V Refer The Amplitude Axis Pr Al HI To choose a channel or channels for spectral analysis click on one or more of the Channel Number buttons beneath the Title bar of the Spectrum window Channels with highlighted depressed buttons are chosen for display If a channel does not contain any data its Channel Number button will be dimmed The whole data display area will be grayed out if no channels are chosen for analysis if there is no selected area or if there is not enough room to show all the chosen channels Individual
316. uttons to allow you to turn the continuous stimulation off and back on again If the stimulus waveform is discrete then the Stimulator panel includes a Stimulate button and the Stimulate button in the Stimulator dialog becomes active This enables you to repeat the discrete stimulus waveform Click Manually to start the stimulator when the Stimulate button is clicked either in the Stimulator dialog or in the Stimulator panel Delay If you wish the delivery of the stimulus waveform to be delayed after you Click Start in the Chart View or Stimulate in the Stimulator dialog or the Stimulator panel enter a delay time from O to 100 seconds into the text box Range Frequency and Pulse Duration For Pulse mode click the PPM pulses per minute or Hz radio button to set the frequency in pulses per minute or hertz respectively It can 70 Chart Software Range Output range s Oms sometimes be more convenient to have frequency stated in terms of minutes The Frequency control is used to set the pulse frequency from 1 to 200 pulses per minute about 0 0167 to 3 333 Hz or per second 0 1 to 200 Hz depending on the radio button chosen above The Pulse duration control sets the time for which the pulse lasts The time is dependent on the frequency set since the pulse duration cannot exceed the period of the stimulus waveform The resolution is 50 ps Range Step Width and Pulse Duration For Step mode click
317. when larger window widths are used Derivative adicht Chart View Idle Channel 400 fs ae AR eo O 0 i z fed Eun z z z a z a 1 The problem of sampling rate The Derivative calculation s setting for window width usually needs adjustment to give a satisfactory slope signal If you then change the sampling rate you will then need to readjust the setting Figure C 6 a shows a signal and an acceptable measure of its slope In c the sampling rate was increased ten times and the horizontal compression increased give a similar scale appearance as in a The unmodified Derivative calculation settings give a poor slope signal 248 Chart Software Figure C 6 The effect of sampling rate on Derivative settings Increasing the window width from 5 to 55 gives a reasonably well smoothed trace With very high sampling rates or very slowly changing signals it may become impossible to produce a satisfactorily smoothed trace of the slope This is partly due to limitations on the maximum width of smoothing or averaging It is also due to the finite number of levels in the digitized signal a Signal sampled at 100 s and displayed at 1 1 b The slope of the signal in a calculated by the Derivative calculation with a window width of 5 c Signal in a sampled at 1000 s and displayed at 10 1 compression d The
318. with one active Chart View not maximized in which you record data Chapter 2 Introduction to Chart 29 Figure 2 7 The components of the Chart View lt iiil a eil Al w Lil zil oil 10 1 20 1 30 1 100 1 00 1 500 1 tks 2ki1 w Application SE Chart Waveforms Chart View Idle Mala EA buttons File Edit Setup Commands Macro Window Help 0 X eSeae ab Sasa aun Document Channel 71 _ ajo7fi987 w t 225 buttons 2 0150 1 oe Date a displa play al optional 2 P as i c325 4 1 T Channel 2 a sil 4 es Minimized channels 1 5 z GEE which can Start gt ete tet a ay P ser also be 944 1 MB hidden The Chart View Below the Title bar and Comments bar there are three main areas in the Chart View from left to right the Amplitude axis area which contains the scale for each channel the data display area which contains recorded data and the channel control area Figure 2 7 Navigating The scroll bar lets you move through the data in the Chart View Click the left or right arrows or drag the box in the scroll bar to move smoothly left or right Click in the region to either side of the box in the scroll bar to jump a screen left or right You can move to the start or end of a recording by choosing Go to Start of Data or Go to End of Data from the Commands menu or typing Ctrl Left arrow or Ctrl Right arrow respectively Buttons i
319. with the settings in the settings file Alternatively you can start Chart without a file by double clicking the Chart desktop shortcut Figure 2 2 or by choosing Chart from the Programs menu of the taskbar s Start button under eDAQ the default location In either case there may be a short delay while Chart sets up the e corder If you start Chart without a file and the Experiments Gallery has been set up the Experiments Gallery dialog may appear at this point close the dialog and ignore it for now its use is described in Chapter 5 When Chart opens the Chart Application window will appear containing the Chart View and any other document windows such as the Zoom View associated with the file When Chart starts up by default the Chart Application window will fill the screen and the Chart View will fill the Chart Application window but the size of each can be adjusted Chart allows you to have up to eight documents open at once but only one such file can be used for recording from the e corder at any one time You cannot open another document while Chart is recording Once Chart is open you can Choose New from the File menu to create and open a new Chart data file If there is no document open a new document is created using the default settings stored by the program settings include the sampling rate input ranges channel areas display settings window sizes etc If there is a document already open the New Document dialog ap
320. xperiments Gallery at startup Appendix A Experiments Gallery Configuration Files 202 264 Chart Software Index 1 4 QNB Data Pad value out of range 136 A Abs Smoothed computed input function 194 AC coupling 52 active point 98 Add Comment dialog 123 Add Comment command 123 Add to Data Pad command 138 adding comments 37 122 123 adding data to the Data Pad 138 advanced features 23 aliasing 14 15 Amplitude axis 31 32 79 82 analysis 23 129 183 analysis mode 11 24 Append command 116 appending files 116 application limits 40 Application window 28 applying settings 117 Arithmetic channel calculation 159 165 Arithmetic dialog 159 Arithmetic command 159 Arrange Icons command 94 Auto Scale command 82 B background recording 38 40 backup files 127 bandwidth 15 16 baseline tracking 188 189 basic data acquisition 13 20 Begin Repeat command 216 Begin Repeat dialog 217 bipolar display 80 blocks 35 appended files 117 lines between 36 84 selecting 99 214 216 settings information 33 C calibration 58 Cascade command 93 channel calculations 158 183 Arithmetic 159 165 Cyclic Measurements 165 170 Derivative 170 172 Digital Filter 173 177 Integral 177 180 Shift 180 Smoothing 181 183 channel controls 32 48 50 Channel Function pop up menu 32 48 50 Arithmetic command 159 Computed Input command 184 Char
321. you to set up the way in which waveform cycles are detected in the same way as you do when using the Cyclic Measurements channel calculation When you make cycle detection settings they apply to all cycle measurements calculated from that channel whether set up in the Data Pad or as a Cyclic Measurements channel calculation This means that multiple columns in the Data Pad showing various cyclic measurements based on a single channel only need to have their cycle detection parameters set up or changed once for the whole lot Any changes made in the Data Pad to the cycle detection settings for a particular Chapter 6 Data Analysis 143 V Refer Transferring Data p 103 channel will affect the Cyclic Measurements calculations based on that channel as well and vice versa Event Count counts the number of events in a selection Cycle Count counts the number of full cycles in a selection This will be zero if there is only one event Average Cyclic Frequency calculates the average frequency of the cycles in the selection in cycles per second Hz Average Cyclic Rate calculates the average frequency of the cycles in the selection in beats per minute BPM Average Cyclic Period calculates the average period of the cycles in the selection Minimum Cyclic Period calculates the minimum period of the cycles in the selection Maximum Cyclic Period calculates the maximum period of the cycles in the selection Average Cyclic Minimum ca
322. z and is suitable for measuring periodic signals of higher frequency than those for which the Ratemeter is used The calculation is done differently to that for the Ratemeter to ensure accuracy The Frequency function works by breaking each second into 20 bins Each time the threshold is crossed from lower to higher the count in the current bin is increased by one That is it counts the number of times the signal crosses the threshold in one direction every 0 05 seconds Chart shows the sum from the last 20 bins This gives a faster and smoother result than if summing were just done for one second For example if recording a 100 Hz signal that changed to 200 Hz over one second you would see the frequency gradually changing from 100 Hz to 200 Hz If results were summed over one second you would just see a jump from 100 Hz to 200 Hz with an intermediate value the average of the two signals Change trom 100 to 200 Hz Change trom 100 to 200 Hz 200 200 180 Lass 100 Lane 50 Lea second o 1 second pe Counter The Counter function just counts transitions from below to above the threshold displaying up to 20 000 registered events versus time It returns to zero when it reaches the range setting For example if the range is set to 200 then after the count reaches 199 the count waveform will reset to O and the count will start again The total cumulative count is obtained by adding the resets multiplying by the range se

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