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Model 735 Intelligent Display User`s Manual

1. SSS PAROSCIENTIFIC INC Tel 425 883 8700 E mail support paroscientific com MODEL 735 INTELLIGENT DISPLAY PART NO MODEL NO RS 232 TRANSDUCER ead TEER GROUND i o A INTERFACE PRESSURE TEMPERATURE D AO POWER p CHASSIS GND a ApS olola TRANSDUCER INTERFACE POWER GROUND OVERPRESSURE lt DC POWER I O DISPLAY OUT ROUND N DISPLAY OUT 6 TO 25 VDC Q HEHHE S DC POWER 1 0 6 25VD0 T____ G LO Too luo Figure 2 Model 735 rear panel The Model 735 rear panel contains the following features AC adapter jack Power and I O terminal block RS 232 port Battery compartment Transducer terminal block Chassis grounding lug Please refer to paragraph 4 2 for detailed information about the Model 735 rear panel features GETTING FAMILIAR 2 4 2 5 2 Model 745 PRESSURE INPUTS M AROSCIENTIFIC INC Tele 8700 E ra suppor paroscientist cor E ZZZ OPEL 745 PORTABLE STANDARD ART ND RS 232 DDEL NO Na SERIAL ND a PRESSURE RANGE ro ROUND OVERPRESSURE EI DISPLAY OUT ROUND 3 DISPLAY DUT4 46 10 42 J De POWER 1 C De E K DC POWER 1 0 didlo ae i im es ha Ap S Tool Fig
2. 5 31 User defined pressure unit label 5 28 PRESSUPE TINIE ica ae deed eck ae 5 20 Serial data unit Suffix ccc ccc cce Li 5 25 Firmware version Li 5 28 Resolution Mmode Li 6 2 Number of significant digits displayed output 6 7 Number of temp readings to average in FIR mode 6 5 Yircoetficient si lino ni lau 5 34 ND COETACIENT 34 1 tt Li censuses eed 5 34 V3 COEMTICIEN tis 4a alla 5 34 Tare serial indication 0 LL 5 26 Tare lock isa cruna oe rita 5 23 Tare SWAtChy States usci asia aaa 5 22 Tare 0ffsetvaliei arsa renano 5 23 NOTES Paroscientific Inc 4500 148 Avenue N E Redmond WA 98052 USA Tel 425 883 8700 Doc Number 8004 001 Fax 425 867 5407 Rev K http www paroscientific com July 2009 E mail support paroscientific com Paroscientific Inc 2009
3. 4 2 Rear Panel 4 2 1 Power Options The Model 735 745 provides three power options AC ADAPTER A 120VAC or 230VAC AC adapter was supplied with the Model 735 745 It plugs into the power jack located in the lower left corner of the rear panel BATTERIES The Model 735 745 can be powered by four AA alkaline batteries A set of batteries was supplied with the unit The battery compartment is located on the rear panel Open the battery compartment by inserting a tool into the small opening at the top of the battery compartment cover and pressing downward while pulling the cover outward Batteries must be installed per the diagram inside the battery compartment The Model 735 745 runs for more than 20 hours on a fresh set of premium AA alkaline batteries The battery level is monitored and LOW BATTERY is displayed on the second line when the batteries are nearly discharged A few hours of operation remain at the time that the LOW BATTERY indication is first displayed WARNING Use only AA alkaline batteries Other types including rechargeable batteries are not recommended WARNING Do not allow batteries to remain in the Model 735 745 for an extended period of time Discharged batteries can become leaky over time and could cause significant damage to the unit It is recommended that batteries be examined periodically for leakage and that any suspect batteries be removed If the unit will not be used for an e
4. Final output pressure value P raw pressure value from pressure equation above PM Value stored in the PM parameter PA Value stored in the PA parameter Units conversion factor Value used to convert psi to the current pressure unit The PM and PA parameters allow you to make minor zero and span adjustments to the raw pressure value Initially PM pressure multiplier is set to 1 0 and PA pressure adder is set to 0 0 Refer to paragraphs 5 7 2 9 and 10 2 for more information PRESSURE MEASUREMENT CONCEPTS 7 10 8 Accessories 8 1 Included Accessories AC POWER SUPPLY The Model 735 745 is delivered with either a 1I0VAC or 220VAC wall power supply If another power supply is to be used ensure that the AC voltage DC voltage current capacity connector type and connector polarity match the original unit SERIAL CABLE The Model 735 745 is delivered with a six foot serial cable Paroscientific PN 6409 003 This cable can be used to connect the Model 735 745 to a standard 9 pin PC RS 232 port DIGIQUARTZ CD LIBRARY The Digiquartz CD ROM Library included in your shipment contains programs that allow you to configure and log data from your instrument These programs will run on any PC with an RS 232 port and the Windows 95 98 NT XP operating system To install the programs insert the CD ROM into your drive A menu will appear on the screen allowing you to select the program you would like to install Run the Digiquartz
5. Interactive program to verify that your hookup is correct and that the instrument is operating properly Run the Digiquartz Assistant program to log data from the instrument Context sensitive help is also available while running each program There are a variety of other useful programs that may be found on the CD ROM You may also use a standard terminal emulation program to interact with your instrument BATTERIES Four AA alkaline batteries are provided ACCESSORIES 8 1 8 2 Optional Accessories MODEL 715 DISPLAY The Digiquartz Model 715 Display can be used with the Model 735 745 to display pressure measurement data at a remote location Refer to paragraph 5 10 for detailed information HIGH PERFORMANCE PRESSURE PORT The high performance DigiPort is now optionally available for use with the Model 765 16B Portable Barometric Standard and all other Digiquartz Barometric Instruments It provides barometric accuracy of better than 0 08 hPa in strong winds all wind directions pitch or tilt angles up to 25 degrees rain and freezing conditions It outperforms open ports single ports single disks shrouded pipes closely spaced dual disks multi hole probes probes incorporating spheres or cones and swiveling pitot tubes with static pressure inlets Figure 5 Digiport mounted on a mast ACCESSORIES 8 2 9 Maintenance The Model 735 745 does not require periodic maintenance other than calibration of the Digiquartz
6. Example A value of 11 results in a pressure integration time of 10 milliseconds and a value of 15 results in a pressure integration time of 20 milliseconds Default 670 Typical set command 0100EW 0100PI 1000 Typical set response 0001PI 1000 Typical read command 0100PI Typical read response 0001PI 1000 Note Whenever the value of PI is changed TI is automatically updated with the same value TI Set or read time based temperature measurement integration time Units Milliseconds Range 1 to 65535 Resolution is 10 milliseconds Values are rounded to the next multiple of 10 Example A value of 11 results in a temperature integration time of 10 milliseconds and a value of 15 results in a temperature integration time of 20 milliseconds Default 670 Typical set command 0100EW 0100TI 1000 Typical set response 0001TI 1000 Typical read command 0100TI Typical read response 0001TI 1000 Note Whenever the value of PI is changed TI is automatically updated with the same value Changing TI has no effect on PI TI should be set to the value as PI for optimum performance in most applications REMOTE OPERATION 5 16 PERIOD BASED INTEGRATION TIME COMMANDS PR TR Set or read period based pressure measurement integration time Units None Range 1 to 16383 Default 238 Typical set command 0100EW 0100PR 200 Typical set response 0001PR 200 Typical read command 0100PR Typical read respon
7. They can be used as stand alone instruments or as part of an RS 232 based data acquisition system The units can be configured using either the front panel user interface or via the RS 232 serial port The front panel user interface provides convenient access to the most often used configuration functions Other configuration functions are accessed via the RS 232 serial port 2 4 Front Panel Features Paroscientific Inc onorF menu 0 Le ENTER Digiquartz Laboratory Standard Model 745 L J L Figure 1 Model 745 front panel The front panel contains the LCD display and the keypad The LCD display shows pressure measurement values on the first line and your choice of several other display options on the second line The keypad provides access to the configuration menu The configuration menu enables the user to quickly and conveniently set up the unit to suit the application Please refer to paragraph 4 1 for more information about configuration menu navigation Please refer to Section 20 for more information about options available via the configuration menu GETTING FAMILIAR 2 3 2 5 Rear Panel Features 2 5 1 Model 735
8. When connecting pressure fittings always use a second wrench to stabilize the pressure fitting on the Model 745 or Digiquartz pressure transducer or permanent damage to the Model 745 or Digiquartz pressure transducer may result WARNING All Digiquartz pressure transducer are designed to operate over a specific pressure range Do not overpressure the Model 745 or Digiquartz pressure transducer or permanent damage may result CAUTION Transducers that are intended to be used in liquid pressure applications are oil filled at Paroscientific If your Model 745 or Digiquartz pressure transducer is oil filled do not pull a vacuum or pressurize with gas or gas bubbles may be introduced into the pressure transducer which will negatively affect its performance Pressure lines connected to oil filled transducers should be filled with clean hydraulic fluid and bled to remove gas bubbles Consult the Model 745 or Digiquartz pressure transducer SCD to determine the oil used to fill the transducer CAUTION Pressure head effects result in zero offsets These effects are more pronounced when liquid filled pressure lines are being used These effects can be minimized by keeping the transducer pressure port and the pressure source at the same elevation or by using the tare or pressure adder functions to make an offset correction to compensate for the pressure head QUICK START 3 6 4 User Interface 4 1 Front Pane
9. cepaslap lire 9 1 10 CALIBRATION ji uil 10 1 10 1 Calibration Procedure denari 10 1 10 2 Zero and Span Adjustments seese 10 1 10 3 Calibrating Other Instruments in 10 3 di WARRANTY agile 11 1 12 SERVICE AND SUPPORT 12 1 13 TROUBLESHOOTING ererrrrrrerrreerseerenecenioneseoo 13 1 14 DISPLAY DATA INTERRUPTED MESSAGE 14 1 15 PRESSURE UNIT CONVERSION TABLE 15 1 16 GLOSSARY_ lie LR an 16 1 17 CONNECTOR DIAGRAMS sooeoesssssosoosossssssssoseosssse 17 1 17 1 Model 735 745 RS 232 Port Connector 17 1 17 2 PC RS 232 Port Connector iii 17 2 17 3 Model 735 745 DC Power I O Terminal Block 17 2 17 4 Model 735 Transducer Interface Terminal Block 17 3 18 WIRING DIAGRAMS eeeossesssssosooesssssssosoosossssssssoseosesse 18 1 18 1 Connecting Digiquartz Transducer to the Model 735 18 1 T8OPRS 29Dis ira ei ci Dl n ia iii di AG NE 18 2 18 3 RS 232 Serial Loop Network 18 2 18 4 Model 715 Display oche dalia laine 18 4 19 HOWDOT 2iinfi alia Laden Li so ESS ke 19 1 20 MENU TREE REFERENCE csccccccccsssssssscsccesees 20 1 21 COMMAND AND PARAMETER REFERENCE 21 1 1 Introduction Thank you for your purchase of a Digiquartz Model 735 Intelligent Display or Model 745 Laboratory Standard Please visit our website at www paroscientific com f
10. 160 4760 13328 0 051 13 328 0 04 24 300 0 04 24 300 9520 26656 0 025 26 656 0 02 48 600 0 02 48 600 16383 45872 0 015 45 872 0 01 83 600 0 01 83 600 Table 2 Relationship of Integration Time Resolution and Sampling Rate for P4 Command PRESSURE MEASUREMENT CONCEPTS 7 7 P7 Command Fast Continuous Pressure Output PR PI Resolution Integration 9600 baud 19200 baud ppm Time s Hz s Hz 8 N A 1 678 168 0 001 79 62 0 013 159 24 0 006 1 3 242 203 0 003 79 62 0 013 159 24 0 006 3 8 80 734 0 008 73 53 0 014 107 30 0 009 4 11 60 551 0 011 73 53 0 014 81 97 0 012 6 17 40 367 0 017 55 25 0 018 55 25 0 018 12 34 20 184 0 034 28 25 0 035 28 25 0 035 24 67 10 092 0 067 14 53 0 069 14 53 0 069 48 134 5 046 0 134 7 37 0 136 7 37 0 136 119 333 2 035 0 333 2 98 0 336 2 98 0 336 238 666 1 018 0 666 1 52 0 660 1 52 0 660 476 1333 0 509 1 333 0 74 1 360 0 74 1 360 1190 3332 0 204 3 332 0 30 3 360 0 30 3 360 2380 6664 0 102 6 664 0 15 6 800 0 15 6 800 4760 13328 0 051 13 328 0 07 13 600 0 07 13 600 9520 26656 0 025 26 656 0 04 26 800 0 04 26 800 16383 45872 0 015 45 872 0 02 45 800 0 02 45 800 PRESSURE MEASUREMENT CONCEPTS Table 3 Relationship of Integration Time Resolution and Sampling Rate for P7 Command PS 0 7 8 7 7 High Speed Sampling See
11. 2 9 Calibration CommandS ee 5 32 5 7 2 10 Diagnostic CommandS e 5 34 5 7 2 11 Global Commands 5 35 5 8 High Speed Samplinp icrlol eo 5 36 5 9 Networking Sirio alii poli ue 5 36 5 9 1 Networking Basics lara 5 37 5 9 2 RS 232 Loop Networking riu ihiraiirivlotuniuno 5 37 5 10 Displaying Data Remotely with Model 715 Display 5 39 6 NANO RESOLUTION FEATURES amp FUNCTIONS 6 1 6 1 Introductio iesen at agi 6 1 6 2 Enabling Nano Resolution n 6 2 6 3 Configuring IIR Filter Mode 6 2 6 4 Configuring FIR Filter Mode 6 4 6 5 Default Numeric Formats for IIR amp FIR Modes 6 6 6 6 Controlling the Numeric Format 6 6 7 PRESSURE MEASUREMENT CONCEPTS 7 1 7 1 Measurement Basics pila eat 7 1 1 2 Meas rement TYPES sca iolanda nai 7 1 73 Sampling VY POS css sate aaa ali 7 3 7 4 Engineering Witaclor 7 4 Ts Tare Pincio eeuu rai 7 4 7 6 Resolution Integration Time and Sampling Rate 7 5 TOL Definitions lalla eli 7 5 402 Inferdependenicies asini ada 7 5 7 7 Highspeed Samplimiy corel 7 9 7 8 Calculations and Formulas 7 9 ACCESSORIES 8 1 8 1 Included Accessonesicntania alata 8 1 8 2 Optional Accessories 2 cccc5s ccc cansdedesecesseadnapavecoudepucdeeussseeneces 8 2 9 MAINTENANCE
12. Check microprocessor clock 5 35 DB Dump buffer ia 5 10 DT Display text on second line 5 30 EW Enable write lai 5 14 P1 Measure single pressure period 5 8 P2 Continuously measure pressure period 5 11 P3 Measure single pressure ene esere eee 5 8 P4 Continuously measure pressure 5 11 P5 Sample and hold pressure seeen 5 10 P6 Sample and hold pressure period 5 10 P7 Continuously measure pressure at maximum rate 5 12 Q1 Measure single temperature period 5 8 Q2 Continuously measure temperature period 5 13 Q3 Measure single temperature eneeeees 5 9 Q4 Continuously measure temperature 5 14 Q5 Sample and hold temperature econ 5 10 Q6 Sample and hold temperature period 5 10 PARAMETERS PAGE Cl Cl eoetficient ara raga avra 5 34 C2 C2 Costicient soil ili iii 5 34 C3 CF cocticienti on Liar 5 34 DI DI COCR CIONE i thea eee ened Ri 5 34 D2 DZ coefficiente natia eas SAG pa ees 5 34 DL Data logger fixed field format mode 5 27 DP Decimal places in displayed pressure value 5 30 IA IIR mode cutoff frequency eeen e
13. Model 735 CAUTION Do not connect transducer ground wire s to the chassis ground terminal Doing so may cause the transducer to produce erratic pressure measurements and or affect the display The chassis ground terminal is meant to terminate cable shields only Note The Digiquartz Data Storage DDS wires if present are not connected to the Model 735 Refer to the SCD that was supplied with the Digiquartz pressure transducer to determine whether DDS wires are present WIRING DIAGRAMS 18 1 18 2 RS 232 Connect the Model 735 745 RS 232 port to a PC RS 232 port per Table 5 below Other RS 232 host devices can be connected to the Model 735 745 in a similar manner consult the manufacturer s documentation for RS 232 port specifications PC Model 735 745 Pin Signal Pin Signal 2 Rx Receive 2 Tx Transmit 3 Tx Transmit 3 Rx Receive 5 Ground 5 Ground Table 5 Model 735 745 RS 232 to PC RS 232 wiring 18 3 RS 232 Serial Loop Network The diagram in Figure 7 illustrates the wiring for a serial loop network of up to 98 Digiquartz Intelligent Instruments and or Transmitters Refer to paragraph 5 9 for more information about serial loop networking If multiple units are to be connected to a common DC power supply run separate power wires from each unit to the power supply This will prevent ground loops that may couple digital switching noise into the Digiquartz pressure transducer re
14. Typical Resolution Ranges Period Resolution is the resolution of pressure and temperature period measurements Measurand Resolution is the statistical resolution limit of the FIR algorithm for pressure and temperature NANO RESOLUTION FEATURES amp FUNCTIONS 6 4 measurements The trigger error typically doubles the least resolution Pressure and Temperature Digits is the total number of digits used to report pressure and temperature measurements Pressure and temperature period measurements contain one additional digit up to a maximum of 13 digits TEMPERATURE SMOOTHING The temperature smoothing function is available for additional low pass filtering of the temperature signal mostly to avoid very rare and small aliasing errors from digital rounding in the FIR mode The XT command enables and disables the smoothing function and controls the corner frequency of the low pass filter Normally the default setting should always be XT 1 no smoothing If temperature smoothing is desired a setting of XT 10 is suggested Temperature smoothing is performed per the following formula Sn aT F 1 a S n 1 Where Sn smoothed temperature Th measured temperature S a 1 smoothed temperature of previous sample a 1 XT XT Set or read the number of temperature measurements to use for temperature smoothing in FIR Mode Range 1 100 Default 1 no smoothing Typical set command 0100EW 0100XT 10 Typical set re
15. example when a PI or TI set command is received the Model 735 745 is configured for time based integration mode when a PR or TR set command is received the Model 735 745 is configured for period based integration The selected integration mode remains in effect until it is changed PERIOD BASED INTEGRATION PR and TR are the period based integration time commands for pressure and temperature signal integration The advantages of PR and TR are that they have higher resolution than the time based integration commands and that they are compatible with earlier generation Digiquartz intelligent transmitters and instruments The resolution of PR and TR is approximately 3 ms TIME BASED INTEGRATION PI and TI are the time based integration time commands for pressure and temperature signal integration The advantage of PI and TI is that the integration time is not a function of measured period and is consistent from unit to unit This allows you to precisely synchronize measurements from two or more Digiquartz intelligent transmitters and instruments that support time based integration The resolution of PI and TI is 10ms PI and TI values are rounded to the nearest multiple of 10ms when used REMOTE OPERATION 5 15 TIME BASED INTEGRATION TIME COMMANDS PI Set or read the time based pressure measurement integration time Units Milliseconds Range 1 to 65535 Resolution is 10 milliseconds Values are rounded to the next multiple of 10
16. is always calculated in C but it is converted to F if TU 1 5 7 2 5 Tare and Overpressure Commands Taring is the process of subtracting a specified value from pressure measurements You may use a measured pressure as the tare value or you may specify any desired value Taring can be enabled disabled and locked out through the use of serial commands RS 232 pressure measurement data can be formatted to include an indication when taring is in effect Refer to the ZI command for more information REMOTE OPERATION 5 21 The overpressure command can be used to specify the overpressure alarm setpoint When the overpressure setpoint is exceeded the overpressure T O line changes from logic low 0 VDC to logic high 5 0 VDC ZS Set or read the tare state parameter value Action The three states of ZS are as follows ZS 0 Taring function is off ZS 1 Taring has been requested but is not yet in effect ZS 2 Taring is in effect ZS is set to 0 on power up If ZL 0 taring is not locked out taring can be requested by setting the ZS to 1 At the first pressure measurement following a tare request the following sequence occurs e The pressure value is stored in the ZV parameter e The value of ZS is set to 2 to indicate that taring is in effect e The value of ZV is subtracted from all subsequent pressure values until taring is turned off If taring is already in effect when a ZS 1 command is issued the sequence described above o
17. keypad is used to move through the menus make selections and change parameter values When in Configuration Menu Mode the first line displays either the menu name or a description of the parameter value being displayed The second line either displays the current menu option or a parameter value The Model 735 745 automatically switches back to Pressure Display Mode if no user input is received for two minutes WARNING Do not attempt to simultaneously access the Model 735 745 through the RS 232 port and the configuration menu Doing so may cause serial commands or configuration menu selections to be ignored 4 1 3 Keypad The functions of the keys are as follows ON OFF KEY e Turns the unit on and off MENU KEY e When in Pressure Display Mode pressing MENU puts the unit in Configuration Menu Mode e When in the configuration menus pressing MENU takes you back to the previous menu level e When in the MAIN MENU pressing MENU takes you back to Pressure Display Mode e When in a parameter edit screen pressing MENU aborts the edit function and takes you back to the previous menu level DOWN ARROW KEY e When in the configuration menus pressing DOWN ARROW scrolls the menu to the next menu option USER INTERFACE 4 2 e When in a parameter entry screen DOWN ARROW decrements the data value UP ARROW KEY e When in a menu pressing UP ARROW scrolls the menu to the previous menu option e When in a paramet
18. least squares regression fit over the sub samples to estimate the best value of pressure While the resolution is statistically two orders of magnitude better than the standard mode it does not suppress aliasing errors A second and usually preferred method is the IIR filter infinite impulse response It consists of a 5 stage digital low pass filter acting on the sub samples It filters all frequencies with a roll off of 100 dB decade above a user selectable cutoff frequency It is an effective anti aliasing filter The inherent resolution depends on the cutoff frequency and not on the sampling period Typically the sampling rate is set at twice the cutoff frequency Nyquist limit NANO RESOLUTION FEATURES amp FUNCTIONS 6 1 6 2 Enabling Nano Resolution Nano resolution can be enabled and disabled by the XM serial command XM Set or read the resolution mode Range 0 Standard Resolution Mode backward compatible 1 Nano resolution IIR Filter Mode 2 Nano resolution FIR Filter Mode Default 0 Typical set command 0100EW 0100XM 1 Typical set response 0001XM 1 Typical read command 0100XM Typical read response 0001XM 1 6 3 Configuring IIR Filter Mode SETTING RESOLUTION Resolution is a function of the cutoff frequency when operating in IIR mode The cutoff frequency is user selectable and is set by the IA command IA Set or read the cutoff frequency setting Range 0 16 Default 11 Typical set
19. network at 9 600 baud or above e Avoid continuous transmission P2 P4 P7 Q2 and Q4 commands at extremely low integration times It is not possible to precisely synchronize measurements from two or more devices by sending a global measurement command This is a result of the delay that occurs as the measurement command propagates through the serial loop When a global command is sent it propagates through the serial loop eventually making its way back to the host Therefore the data received by the host in response to a global command includes the command itself followed by the individual responses from all devices on the network 5 38 5 10 Displaying Data Remotely with Model 715 Display The Model 715 Display can be used to replicate the Model 735 745 display data at a distance of up to 4000 feet The Model 715 display is identical to that of the Model 735 745 with the following exceptions e Pressure rate of change data cannot be displayed on the Model 715 If the Model 735 745 is set up to display pressure rate of change the second line of the Model 715 will not be updated e When the Model 735 745 configuration menu is accessed the Model 715 will not display the configuration menu but will continue to display pressure values Using the Model 715 with the Model 735 745 is simple and easy Simply connect the units as shown in paragraph 0 Turn on the Model 735 745 then turn on the Model 715 The Model 715 will autom
20. of these and other software programs are also available at the Paroscientific web site at www paroscientific com 5 2 1 Digiquartz Interactive 2 0 DQI 2 0 Digiquartz Interactive 2 0 is a Windows program that makes it easy to communicate with and configure DIGIQUARTZ Intelligent devices We encourage you to install DQI 2 0 and use it to verify proper device REMOTE OPERATION 5 1 operation configure your device take measurements and experiment with its functions DQI 2 0 is separated into two main sections Configuration and Monitoring and Digiquartz Terminal The Configuration and Monitoring section provides a means of viewing changing storing and retrieving the configuration parameters of your instrument It also allows you to take measurements and display them numerically and in a real time graph Measurement data may also be logged to a text file in a format that can be easily imported into popular PC programs such as Microsoft Excel or Word The Digiquartz Terminal section allows you to interactively communicate with your instrument using text based commands Measurement data may be logged to a text file in a format that can be easily imported into popular PC programs such as Microsoft Excel or Word 5 2 2 Digiquartz Assistant DQA Digiquartz Assistant is a Windows data logging program With DQA you can log time stamped measurement data from up to 8 Digiquartz intelligent devices Measurement d
21. paragraph 5 8 for techniques that can be used to increase sampling rate 7 8 Calculations and Formulas The Model 735 745 calculates internal sensor temperature and temperature compensated pressure from period measurements of the Digiquartz pressure transducer output signals The equations and coefficients used to perform these calculations are given below The Model 745 is initialized with its transducer coefficients at the factory the user must initialize the Model 735 with its transducer coefficients prior to taking pressure measurements TEMPERATURE CALCULATION The following equation is used to calculate internal sensor temperature T Y U Y2U 3U Where T Temperature C U temperature period microseconds at 0 C U temperature period microseconds Up microseconds Temperature coefficients Up Yi Yo Y3 PRESSURE CALCULATION The following equation is used to calculate pressure PHC 1 Da tae Where P pressure T pressure period microseconds U temperature period microseconds Up microseconds C C CU CGU D D DU To T TU T3U Ty T U PRESSURE MEASUREMENT CONCEPTS 7 9 Pressure coefficients Ci C2 C Di Dy Ti To T T Ts FINAL OUTPUT PRESSURE CALCULATION The following equation is used with the pressure value calculated above to calculate the final output pressure value P output PM units conversion factor P PA Where Poutpu
22. pressure period measurement in units of microseconds Action Measure pressure period send pressure period value and await next command Typical command 0100P1 Typical response 000128 123456 Value 28 123456 Note Repeatedly issuing the P1 command will temporarily prevent the front panel display from being updated Sample and send one pressure measurement in selected engineering units Action Measure temperature period measure pressure period calculate temperature compensated pressure send pressure value and await next command Typical command 0100P3 Typical response 000114 71234 Value 14 71234 REMOTE OPERATION 5 8 Q1 Sample and send one temperature period measurement in units of microseconds Action Measure temperature period send temperature period value and await next command Typical command 0100Q1 Typical response 00015 1234567 Value 5 1234567 Note Repeatedly issuing the Q1 command will temporarily prevent the front panel display from being updated Q3 Sample and send one temperature measurement in selected engineering units Action Measure temperature period calculate temperature send temperature value and await next command Typical command 0100Q3 Typical response 000122 345 Value 22 345 Note Repeatedly issuing the Q3 command will temporarily prevent the front panel display from being updated 5 7 1 2 Sample and Hold Measurement Commands The following commands a
23. pressure transducer If the unit becomes soiled it may be cleaned using a soft cloth lightly moistened with plain water WARNING WARNING Do not allow liquids to enter the enclosure Electronic failure may result Do not open the enclosure No user serviceable parts are located inside Your warranty will be voided if the enclosure is opened MAINTENANCE 9 1 10 Calibration 10 1 Calibration Procedure Paroscientific transducers measure pressure with a force sensitive quartz crystal whose output period or frequency changes with applied load For a given temperature true applied pressure will generate a specific crystal period Therefore a measure of the crystal period will indicate what pressure is applied provided the relationship between crystal period and pressure is known This relationship is usually expressed as the C D Ty equation C D and Ty are coefficients that are unique to Paroscientific transducers and are different for each transducer In addition these coefficients are characterized for thermal effects For each temperature they are expressed as polynomial expansions with coefficients Cl C2 C3 D1 D2 T1 T2 T3 T4 and T5 Typically it takes between 7 and 10 coefficients to fully describe the relationship also called the CD thermal model between crystal output temperature and pressure Recalibration is necessary if a user decides that the agreement between true and indicate
24. that the pressure units be set to psi UN 1 prior to setting PF Refer to paragraph 5 7 2 4 for more information about setting pressure units QUICK START 3 3 CAUTION PF must be set to the full scale pressure value of the Digiquartz transducer Failure to do so will result in improper formatting of pressure measurement values The example below is for a 45 psi transducer Typical set command 0100EZ 0100PF 45 Typical set response 0001PF 45 00000 e Set the transducer overpressure limit value PL is typically set to 1 2 times the full scale pressure value of the Digiquartz transducer Refer to the transducer Specification Control Drawing for specific overpressure limits PL is always set and reported in psi regardless of the pressure unit setting The example shown below is for a 45 psi transducer 45 x 1 2 54 Typical set command 0100EZ 0100PL 54 Typical set response 0001PL 54 00000 e Set the transducer type value Set PO according to the Digiquartz pressure transducer type absolute gauge or differential The table below shows the integer values used with PO to identify the transducer type QUICK START 3 4 PO value Transducer type 0 Absolute l Gauge 2 Differential The following example assumes an absolute transducer Typical set command 0100EZ 0100PO 0 Typical set response 0001PO 0 e Set the transducer serial number value Set SN to the serial number ind
25. the calibration coefficients of the particular Digiquartz pressure transducer to which it is connected incorrect pressure measurement values will be displayed and the overpressure alarm may sound QUICK START 3 1 Step 4 Establish communications between the Model 735 and a PC Install Digiquartz Interactive 2 0 on your PC Digiquartz Interactive 2 0 can be installed from the Digiquartz CD Library that was included with your Model 735 or downloaded at the Paroscientific web site at www paroscientific com Connect the RS 232 port of your Model 735 to the RS 232 port of your PC and power up the instrument Run Digiquartz Interactive 2 0 Select the Digiquartz Terminal option and click Next You send commands to the unit by typing them into the Command field Responses to commands will be displayed in the Response window If you are unable to establish communications refer to the DQI online help information and Section 13 of this manual Step 5 Configure the Model 735 with the Digiquartz pressure transducer coefficients and parameters Please refer to Section 5 for more information about configuration commands and their use Set the overpressure alarm setpoint The overpressure alarm setpoint OP is set to 0 0 psi at the factory OP is set in the current pressure units We recommend that the pressure units be set to psi UN 1 prior to setting OP refer to paragraphs 5 7 2 4 for details about setting pressure u
26. the temperature measurement interval used by the P7 command Action Controls how often temperature measurements are taken during a P7 pressure measurement sequence If PS 0 an initial temperature measurement is taken and all subsequent pressure measurements are compensated using that value If PS 1 a temperature measurement is taken before each pressure measurement same as P4 If PS n and n gt I an initial temperature measurement is taken and subsequent temperature measurements are taken after every n pressure measurements Range 1 to 65535 Typical command 0100EW 0100PS 4 Typical response 0001PS 4 Note When setting virtually all parameter values you must precede the command with an EW Enable Write command Please refer to paragraph 5 7 2 1 for more information Continuously sample and send temperature period measurement values in units of microseconds Action Measure temperature period send temperature period value and repeat until commanded to stop Typical command 0100Q2 Typical response 00015 1234567 Value 5 1234567 00015 1234568 Value 5 1234568 00015 1234567 Value 5 1234567 Note The Q2 command will temporarily prevent the front panel display from being updated REMOTE OPERATION 5 13 Q4 Continuously sample and send temperature measurement values in selected engineering units Action Measure temperature period calculate temperature send temperature value and repeat unt
27. 0100MD Typical read response 0001MD 1 CAUTION If MD is set to 0 or 2 the front panel display will no longer be updated For most applications MD should only be set to 1 or 3 MD settings of 0 and 2 are supported only for compatibility with other Digiquartz Intelligent Instruments REMOTE OPERATION 5 18 Note When MD is set to a non zero value the specified data output mode will be preempted under the following conditions e Continuous serial pressure data output is suspended when a measurement command is received Continuous data output resumes when the measurement command is complete e Display data output is suspended when a period measurement command P1 P2 P6 Q1 Q2 Q6 is received Display data output resumes when the period measurement command is complete e Continuous pressure data output is suspended when a continuous measurement command P2 P4 P7 Q2 Q4 is received and resumes when the continuous measurement command is cancelled REMOTE OPERATION 5 19 5 7 2 4 Engineering Units Commands Engineering units commands are used to specify the engineering units to be used when calculating pressure or temperature values and to configure the user defined pressure unit UN Set or read the pressure engineering units Action Sets or queries the conversion factor by which all calculated pressure values are multiplied before being output Setting UN to a non zero value selects one of eight standa
28. 232 Pressure measurements are fully temperature compensated and therefore require an internal temperature measurement When a pressure measurement is made the following sequence occurs e The temperature signal period is measured e An internal transducer temperature value is calculated using the temperature period and the calibration coefficients e The pressure signal period is measured e A temperature compensated pressure value is calculated using the pressure period temperature value and the calibration coefficients e The pressure value is displayed and optionally output via RS 232 INTERNAL SENSOR TEMPERATURE MEASUREMENTS Internal sensor temperature is normally only used for temperature compensation of pressure but can be requested independently for diagnostic and other purposes Internal sensor temperature measurements can optionally be displayed on the bottom line of the Model 735 745 display and can also be output via RS 232 When an internal sensor temperature measurement is made the following sequence occurs e The temperature signal period is measured e A temperature value is calculated using the temperature period and the calibration coefficients e The temperature value is optionally displayed and or output via RS 232 PRESSURE MEASUREMENT CONCEPTS 7 2 PRESSURE AND TEMPERATURE PERIOD MEASUREMENTS Period measurements are used mainly for calibration and diagnostic purposes but may be useful in high speed sa
29. 300 42 600 23 1200 14 2400 9 4800 6 9600 5 19200 5 Table 4 P3 minimum delay TROUBLESHOOTING 13 2 MENUS ARE NOT AS RESPONSIVE AS THEY ONCE WERE e The Model 735 745 communicates internally at the same baud rate as the RS 232 port This can cause the Configuration Menu to react slower at low baud rates We recommend that you operate the Model 735 745 at a minimum of 9600 baud for optimum responsiveness RS 232 COMMANDS ARE IGNORED e Do not attempt to simultaneously access the Model 735 745 through the RS 232 port and the Configuration Menu Doing so may cause serial commands or Configuration Menu selections to be ignored CONFIGURATION MENU SELECTIONS ARE IGNORED e Do not attempt to simultaneously access the Model 735 745 through the RS 232 port and the Configuration Menu Doing so may cause serial commands or Configuration Menu selections to be ignored DIGIQUARTZ INTERACTIVE DQI CANNOT DETECT MODEL 735 745 e Check that power is being applied to the Model 735 745 If pressure values are being displayed the unit is being powered e Check that the Model 735 745 is connected to the specified com port e Check that the RS 232 connections between the Model 735 745 and the PC are correct If in doubt use the serial cable that was provided with your Model 735 745 TROUBLESHOOTING 13 3 14 Display Data Interrupted Message Under certain circumstances the Model 735 745 is unable to update its pressure value di
30. 745 that is to receive the command 00 Source ID ID of the device that is sending the command Serial host is ID 00 P3 Command P3 is an example Refer to paragraph 5 7 for descriptions of the entire command set Cr Carriage return ASCII 13 Lf Linefeed character ASCII 10 RESPONSE FORMAT Responses are typically received in the following format 000114 4567CrLf REMOTE OPERATION 5 4 Where Start character Asterisk ASCH 42 00 Destination ID ID of the serial host that is to receive the response 01 Source ID ID of Model 735 745 that is responding 14 4567 Data Data sent in response to the prior command Cr Carriage return ASCII 13 Lf Linefeed character ASCII 10 These examples are typical Refer to paragraph 5 7 for specific details regarding each available command 5 5 Establishing RS 232 Communications The following are two methods of establishing and verifying RS 232 communications between the Model 735 745 and a PC USING DIGIQUARTZ INTERACTIVE 2 0 SOFTWARE The easiest way to establish RS 232 communications is by using Digiquartz Interactive 2 0 DQI 2 0 software Step 1 Connect the Model 735 745 to the PC Connect the Model 735 745 RS 232 port to the PC RS 232 port using the serial cable Paroscientific PN 6409 003 that was provided with the unit Any other standard RS 232 serial cable intended for use with the PC can also be used Step 2 Install DQI 2 0 Insert the Digiquartz CD Li
31. 8 12 34 20 184 0 034 28 49 0 035 28 49 0 035 24 67 10 092 0 067 14 62 0 068 14 62 0 068 48 134 5 046 0 134 7 37 0 136 7 37 0 136 119 333 2 035 0 333 2 98 0 336 2 98 0 336 238 666 1 018 0 666 1 52 0 660 1 52 0 660 476 1333 0 509 1 333 0 74 1 360 0 74 1 360 1190 3332 0 204 3 332 0 30 3 360 0 30 3 360 2380 6664 0 102 6 664 0 15 6 800 0 15 6 800 4760 13328 0 051 13 328 0 07 13 600 0 07 13 600 9520 26656 0 025 26 656 0 04 26 600 0 04 26 600 16383 45872 0 015 45 872 0 02 45 800 0 02 45 800 Table 1 Relationship of Integration Time Resolution and Sampling Rate for P2 Command 7 6 PRESSURE MEASUREMENT CONCEPTS P4 Command Continuous Pressure Output PR PI Resolution Integration 9600 baud 19200 baud ppm Time uz s Hz 8 N A 1 678 168 0 001 79 62 0 013 159 24 0 006 1 3 242 203 0 003 79 62 0 013 153 37 0 007 3 8 80 734 0 008 60 35 0 017 60 35 0 017 4 11 60 551 0 011 46 08 0 022 46 08 0 022 6 17 40 367 0 017 30 49 0 033 30 49 0 033 12 34 20 184 0 034 15 58 0 064 15 58 0 064 24 67 10 092 0 067 7 96 0 126 7 96 0 126 48 134 5 046 0 134 4 07 0 246 4 07 0 246 119 333 2 035 0 333 1 64 0 608 1 64 0 608 238 666 1 018 0 666 0 82 1 220 0 82 1 220 476 1333 0 509 1 333 0 41 2 440 0 41 2 440 1190 3332 0 204 3 332 0 16 6 080 0 16 6 080 2380 6664 0 102 6 664 0 08 12 160 0 08 12
32. B command is received Sample and hold one temperature period measurement in units of microseconds Action Measure temperature period save temperature period value and await DB command Typical command 0100Q6 Typical response No response until DB command is received Dump Buffer Send a held measurement value Action If a measurement value is being held send it otherwise do nothing Typical command 0100DB Typical response 000114 12345 Value 14 12345 REMOTE OPERATION 5 10 5 7 1 3 Continuous Measurement Commands The following commands are used to initiate and control continuous measurements Continuous measurement commands repeatedly take measurement samples and return measurement values until commanded to stop Continuous measurements are cancelled by sending any valid command P2 P4 Continuously sample and send pressure period measurement values in units of microseconds Action Measure pressure period send pressure period value and repeat until commanded to stop Typical command 0100P2 Typical response 000128 123456 Value 28 123456 000128 123457 Value 28 123457 000128 123456 Value 28 123456 Note The P2 command will temporarily prevent the front panel display from being updated Continuously sample and send pressure measurement values in selected engineering units Action Measure temperature period measure pressure period calculate temperature compensated pressur
33. ENU scroll to Aux Menu and select it using the Enter key Scroll the AUX MENU to Unit ID and select it using the Enter key Note the unit ID Press the MENU key to return to the AUX MENU Scroll the AUX MENU to Baud Rate and select it using the Enter key Note the baud rate you may change the baud rate using the UP ARROW and DOWN ARROW keys Press the ENTER key to return to Pressure Display mode Step 4 Configure the terminal program Set the com port to the PC com port number that you are using Set the baud rate to match the Model 735 745 Set the communications protocol to 8 data bits no parity and 1 stop bit If DQT is not being used it is often necessary to configure the terminal program to append a line feed character to each carriage return character At this point the terminal program should be able to communicate with the unit Refer to paragraph 5 7 for detailed command and response information Refer to the DQT reference feature for detailed information about using DQT REMOTE OPERATION 5 6 5 6 Setting and Reading Parameter Values The behavior of the Model 735 745 is controlled by several operating parameters The values of these parameters are stored in non volatile memory Commands are provided to set and read the parameters values Refer to paragraph 5 7 2 for detailed information about the various parameters SETTING PARAMETER VALUES Each parameter set command must be preceded with the EW enable write command Th
34. Line 2 No information is displayed on the second line The second line can also display an overpressure warning if the measured pressure exceeds the limits of the Digiquartz pressure transducer The overpressure warning is not available when the external text display option has been selected Depending on the second line display option the overpressure warning is either OVERPRESSURE or OVPR 4 1 4 4 Aux Menu SAMPLING TIME Selects the measurement sampling time The range is 002 to 131 07 seconds in 002 second increments UNIT ID Selects the unit ID for networking applications The range is 01 to 98 PASSWORD Selects the password required to change settings within the Configuration Menu The password is a four digit integer value When the password value is 0000 the password function is disabled and no password is required to change settings When the password value is non zero the password will be requested each time a setting is to be changed If the proper password is entered the setting can be changed if not you will be returned to the menu Contact Paroscientific if you are unable to configure your Model 735 745 due to a lost password USER INTERFACE 4 5 VERSION Displays the firmware versions This information may be helpful for diagnostic purposes BAUD RATE Selects the RS 232 baud rate The following options are available e 19200 9600 4800 2400 1200 600 300 USER INTERFACE 4 6
35. ON 5 23 OP Set or read the overpressure alarm setpoint value Action When a pressure measurement value is less than the value of OP the overpressure I O line is at logic low 0 VDC and the overpressure alert is silent if it is greater or equal to the value of OP the overpressure I O line is set to logic high 5 0 VDC and the overpressure alert sounds OP is set in the current pressure units and is scaled accordingly if the engineering units are changed Range 9999999 to 9999999 Default Maximum rated unit pressure Typical set command 0100EW 01000P 15 Typical set response 00010P 15 00000 Typical read command 01000P Typical read response 00010P 15 00000 5 7 2 6 Measurement Data Formatting Commands These commands are used to alter the format of serial measurement data The following data formatting functions are available e Append engineering units to pressure and temperature measurement data e Append a taring indication to tared pressure measurement data e Add underscores to separate the measurement data from the rest of the serial output data string to improve readability e Add trailing zeroes to the measurement data to create a fixed length data string to simplify parsing Formatting commands can be used separately or in any combination REMOTE OPERATION 5 24 US Set or read the engineering units suffix parameter value Action When US 1 an engineering units label is appended to pressure and temperatur
36. Paroscientific Inc Digiquartz Pressure Instrumentation User s Manual for Model 735 Intelligent Display And Model 745 High Accuracy Laboratory Standard The standard by which other standards are measured Technology TABLE OF CONTENTS Page 1 INTRODUCTION ite 1 1 Ik VLatesticaltes a alain i 1 1 12 COTY EM nihil 1 1 1 3 Warnings and Safety Precautions 1 2 2 GETTINGFAMILIAR uri 2 1 Del Physical Inspectio li arcana 2 1 2 2 Product Features and Configurations 2 1 2 3 Physical DESCHpHnon ii aaa lina 2 2 2 4 Front Panel Features 2 3 2 5 Rear PanelFealres naar 2 4 Dard Modellare ana 2 4 2 52 Modeb 4d is lieta lata 2 5 3 QUICKSTART fliiablo iii aa 3 1 db Model T4 Joncar Saeed oovecteralnaaeatinsuenct a ni 3 1 3 2 Model FAS acoso ezio iano ilo ile 3 1 3 3 Applying Pressure lio aiadadanecakseadeon 3 5 4 USER INTERFACE esesscesesccssescsscssesccsossesocssssosoossesossoe 4 1 4 ProntPalel sso 4 1 AMET Dispari 4 1 4 1 2 Operating Modes ala idta 4 1 AES ROSPI Lira italo 4 2 4 1 4 Configuration Menu Options 4 3 ddl Fare Meisene ae a a 4 3 4142 Units Menisi elica 4 4 4 1 4 3 Display Menia 4 4 ATAA AMA cati 4 5 42 SRG AP Ame ees tig cece seal sasha es ce ha a 4 7 4 2 1 PowerOptions assiali 4 7 4 2 2 Terminal Block Desernptions irta 4 8 And Overpressure ALI ili a 4 8 REMOTE OPERATION csccssc
37. al transducer temperature The Model 735 745 measures these signals using a technique similar to that of a common laboratory frequency counter Like the frequency counter a signal must be integrated or sampled for a specified period of time to measure its period The time over which the signal is sampled determines the resolution of the measurement Longer sampling times increase resolution but result in a slower sampling rate The Model 735 745 allows you to set the integration time between 0 001 and 65 535 seconds Pressure and temperature integration times can be set independently You can use these features to configure the unit according to the data acquisition and resolution requirements of your application Refer to paragraph 7 6 for more information about integration time resolution and sampling rate 7 2 Measurement Types One or both of the Digiquartz pressure transducer output signals are sampled depending on the type of measurement requested Four types of measurements can be taken e Pressure e Internal sensor temperature e Pressure period e Temperature period Pressure measurements are displayed by the Model 735 and 745 The other types of measurements can only be accessed via the RS 232 port PRESSURE MEASUREMENT CONCEPTS 7 1 PRESSURE MEASUREMENTS Pressure measurements are the most common Pressure measurement values are displayed on the top line of the Model 735 745 display and can also be output via RS
38. ales and application engineers at support paroscientific com or 425 883 8700 If you are sending an instrument to us for service please check our web site under the service section about the details of how to ship a unit to us for service SERVICE AND SUPPORT 12 1 13 Troubleshooting This section will help you to diagnose common problems related to the Model 735 745 If you have taken the recommended action and you are still experiencing difficulty please contact an Application Engineer at Paroscientific MODEL 735 745 DOES NOT POWER UP WHEN ON OFF KEY IS PRESSED If AC adapter is being used check that the adapter is plugged into the power jack on the rear panel and is plugged into an appropriate AC outlet If batteries are being used check that the batteries are fresh and check that the batteries are installed per the diagram on the inside of the battery compartment If the unit is powered via the DC POWER I O terminal block check that power and ground are connected per the terminal block pinout on the rear panel label and check that DC power is actually being supplied to the unit MODEL 735 745 POWERS UP BUT DOES NOT DISPLAY PRESSURE VALUES Model 735 ONLY Check that the Digiquartz pressure transducer is properly wired to the Model 735 transducer interface Refer to the interface pinout on the rear panel label Check that the MD parameter is set to 1 or 3 If MD is set to 0 or 2 the pressure display will not be
39. ata can also be displayed in real time in an automatically scaled graph Data is stored to a text file in a format that can easily be imported into popular PC programs such as Microsoft Word or Excel Refer to the help function in DQA for more information 5 2 3 Digiquartz Terminal DQT Digiquartz Terminal is a Windows terminal program that was developed specifically for use with Digiquartz intelligent devices Like traditional terminal programs Digiquartz Terminal lets you interactively communicate with intelligent devices In addition Digiquartz Terminal can log time stamped measurement data to a text file in a format that can easily be imported into popular PC programs such as Microsoft Word or Excel Refer to the help function in Digiquartz Terminal for more information REMOTE OPERATION 5 2 5 3 Command and Response Basics The Model 735 745 is remotely controlled by serial ASCII command strings The following basic tasks can be accomplished by sending the appropriate command e Take a measurement e Perform a control function such as locking the baud rate e Set an operating parameter such as integration time e Read the value of an operating parameter When setting virtually all parameter values you must precede the command with an EW command This prevents accidental alteration of stored parameter values Please refer to paragraphs 5 6 and 5 7 2 1 for more information about the EW command Measurement commands typi
40. atically synchronize its baud rate to that of the Model 735 745 this may take as much as a few minutes When the Model 715 has synchronized it will begin to replicate the Model 735 745 display REMOTE OPERATION 5 39 6 Nano Resolution Features amp Functions 6 1 Introduction With firmware revision D1 06 or later it is now possible to achieve parts per billion resolution nano resolution This feature can be enabled by software command When disabled the sensor is backward compatible and works in the standard mode with typical parts per million resolution Nano resolution is achieved by sub sampling the pressure at a much higher rate typically 8 kHz and applying digital signal processing techniques Because of the much higher processing requirements more input power is required In general the nano resolution feature is only useful if the pressure is stable enough over the effective sampling period and if the data acquisition system can handle additional digits The practical bandwidth of interest is in the infrasound and deep infrasound 10 to 0 001 Hz Two methods for nano resolution are available The first method processes the sub samples in a finite time interval analogous to the integration time of the standard mode The digital process is an FIR filter finite impulse response The resolution can be directly compared to the resolution of the standard mode at the same sampling rate synchronized The algorithm performs a
41. brary CD into your CDROM drive and follow the installation instructions Step 3 Run DQI 2 0 Power up the Model 735 745 and run DQI 2 0 At the Startup screen select the PC com port number that you are using and click the Detect button DQI 2 0 will search for the unit and establish communications with it automatically Click the OK button to exit the Startup screen and enter DQI 2 0 At this point DQI 2 0 should be able to communicate with the unit Refer to the DQI 2 0 help feature for more information about using DQI 2 0 REMOTE OPERATION 5 3 USING A TERMINAL PROGRAM A standard terminal program can also be used to establish RS 232 communications with the Model 735 745 Digiquartz Terminal DQT software can be used for this purpose DQT is provided on the Digiquartz CD Library CD Step 1 Connect the Model 735 745 to the PC Connect the Model 735 745 RS 232 port to the PC RS 232 port using the serial cable Paroscientific PN 6409 003 that was provided with your unit Any other standard RS 232 serial cable intended for use with the PC can also be used Step 2 Install DQT Insert the Digiquartz CD Library CD into your CDROM drive and follow the installation instructions Any other terminal program already installed on your PC can also usually be used Step 3 Determine the current baud rate and ID settings of your Model 735 745 Power up your unit and press the MENU key to enter Configuration Menu mode From the MAIN M
42. cally generate a response that contains the measurement data Parameter set commands typically generate a response that reports the updated parameter value Parameter read commands report the current parameter value When a command is received any command that is in progress will be aborted This enables you to send an RS 232 command to the Model 735 745 at any time regardless of its current activity 5 4 Command and Response Format In general RS 232 commands and responses are made up of the following START CHARACTER e The start character is an asterisk ASCII 42 DESTINATION ID e The destination ID identifies the device that is to receive the command or response e The destination ID is a two digit integer between 00 and 99 ID 00 is reserved for the serial host usually a PC SOURCE ID e The source ID identifies the device that is sending the command or the response REMOTE OPERATION 5 3 e The source ID is a two digit integer between 00 and 98 ID 00 is reserved for the serial host usually a PC COMMAND OR RESPONSE DATA e A wide variety of commands and resulting response data are available Refer to paragraph 5 7 for detailed information TERMINATION CHARACTERS e The termination characters are carriage return ASCII 13 and linefeed ASCII 10 COMMAND FORMAT Commands are typically sent in the following format 0100P3CrLf Where Start character Asterisk ASCH 42 01 Destination ID ID of the Model 735
43. ccurs and taring continues using a new value of ZV Taring can be turned off by issuing a ZS 0 command Range 0to2 Default 0 Typical set command 0100EW 0100ZS 1 Typical set response 0001ZS 1 Typical read command 0100ZS Typical read response 0001ZS 1 REMOTE OPERATION 5 22 ZN ZL Set or read the tare value Action Sets or queries the value that is subtracted from pressure measurements when taring is activated ZV can be set to any desired value when taring is in effect ZS 2 Note however that if taring is subsequently requested a new value will overwrite the ZV value you have set The value of ZV is set to 0 on power up Range 9999999 to 9999999 Default 0 Typical set command 0100EW 0100ZV 14 7123 Typical set response 0001ZV 14 7123 Typical read command 0100ZV Typical read response 0001ZV 14 7123 Set or read the tare lockout parameter value Action When ZL 0 ZS can be set to enable and disable taring When ZL 1 taring is locked and the value of ZS cannot be modified via serial commands or the Tare Input I O line However if ZS 1 and a ZL 1 command is issued taring will be in effect when the next pressure measurement is taken but you cannot turn taring off until ZL is set to 0 The value of ZL is set to 0 on power up Range Oorl Default 0 Typical set command 0100EW 0100ZL 1 Typical set response 0001ZL 1 Typical read command 0100ZL Typical read response 0001ZV 1 REMOTE OPERATI
44. command 0100EW 0100IA 11 Typical set response 0001IA 11 Typical read command 0100IA Typical read response 0001IA 11 See Table 1 for a list of ranges for IA values cutoff frequencies measurement resolution and the number of digits reported via RS 232 NANO RESOLUTION FEATURES amp FUNCTIONS 6 2 Table 1 IIR Filter Mode Typical Resolution Ranges Cutoff frequency is the 3dB point of the low pass IIR filter Effective Time Interval is the recommended minimum time interval between measurements that ensures sampling up to the specified cutoff frequency The time interval is set using the PI command Period Resolution is the resolution of pressure and temperature period measurements Measurand Resolution is the resolution of pressure and temperature measurements Pressure and Temperature Digits is the total number of digits used to report pressure and temperature measurements Pressure and temperature period measurements contain one additional digit NANO RESOLUTION FEATURES amp FUNCTIONS 6 3 6 4 Configuring FIR Filter Mode SETTING RESOLUTION Resolution is a function of the integration time when operating in FIR mode The integration time is set by the PI command Refer to page 5 7 2 2 for more information about the PI command Table 2 lists various PI values and the resulting measurement resolution for pressure period pressure and the number of digits reported via RS 232 Table 2 FIR Filter Mode
45. culated using original calibration coefficients in the current pressure units PM the current value of the PM parameter PA the current value of the PA parameter PA Set or read the pressure adder parameter Action The pressure adder parameter is used to make zero adjustments to the calibration PA can also be used to offset absolute pressure measurements by atmospheric pressure to obtain gauge pressure Range 9999999 to 9999999 Default 0 0 Typical set command 0100EW 0100PA 0000123 Typical set response 0001PA 0000123 Typical read command 0100PA Typical read response 0001PA 0000123 REMOTE OPERATION 5 32 PM TC Note The value of PA is entered in the current pressure units but is converted to psi prior to being stored When PA is queried it returns the value scaled to the current pressure units Set or read the pressure multiplier parameter Action The pressure multiplier parameter is used to make span adjustments to the calibration Range 9999999 to 9999999 Default 1 Typical set command 0100EW 0100PM 1 000123 Typical set response 0001PM 1 000123 Typical read command 0100PM Typical read response 0001PM 1 000123 Note The value of PM is dimensionless and is therefore not scaled if the units are changed Read the crystal timebase correction factor Action TC is used to normalize the nominal 14 7456 MHz reference crystal frequency to 10 MHz to compensate for the natural variat
46. d pressure is outside tolerances set for the particular application Please see the documents entitled Recalibration of Paroscientific Transducers Doc 8140 001 and Calibration of Digiquartz Sensors at www paroscientific com for recalibration procedures and calibration software support 10 2 Zero and Span Adjustments The Paroscientific transducer measures a force that is generated by external pressure Since the quartz crystal is extremely sensitive any other small force that is transmitted to the sensing element will be added to the pressure measurement A pressure offset generated in this way is purely additive and is the same at all pressure values In principle checking accuracy at a single applied pressure is sufficient to determine an offset Of course the offset can be calculated as the average offset of many pressure points Span is defined here as the pressure difference from minimum pressure to full scale pressure A span error is the difference between the indicated pressure span as measured by the transducer and the true pressure span If CALIBRATION 10 1 a transducer is carefully adjusted at minimum pressure the span error is simply the difference between indicated and true applied pressure at full scale The span of a Paroscientific transducer is rarely adjusted since the scale factor of the sensing element is very stable Differences are sometimes due to different calibration standards The span of a dead weight tes
47. del 735 Transducer Interface Terminal Block Terminal Signal Transducer wire color 1 Transducer power Red 2 Pressure Blue Black twisted with blue 2 eoa Black twisted with white 4 Temperature White 5 Chassis ground CAUTION Do not connect transducer ground wire s to the chassis ground terminal Doing so may cause the transducer to produce erratic pressure measurements and or affect the display The chassis ground terminal is meant to terminate cable shield only Refer to paragraph 18 1 for more information about connecting a Digiquartz Pressure Transducer to a Model 735 CONNECTOR DIAGRAMS 17 3 18 Wiring Diagrams 18 1 Connecting Digiquartz Pressure Transducer to the Model 735 Connect the Digiquartz Pressure Transducer to the Model 735 per Figure 6 below Low capacitance shielded twisted pair cable is recommended Twisted pairs from the transducer should correspond with twisted pairs within the cable The maximum length of cable that can be used depends on the cable capacitance Refer to paragraph 17 4 for more information regarding the Transducer Interface Terminal Block 1 POWER CABLE FROM DIGIQUARTZ PRESSURE TRANSDUCER 2 SIGNAL 3 GROUND TEMP SIGNAL 5 CHASSIS GROUND CABLE SHIELD IF PRESENT MODEL 735 TRANSDUCER INTERFACE TERMINAL BLOCK Figure 6 Wiring Digiquartz transducer to
48. e send pressure value and repeat until commanded to stop Typical command 0100P4 Typical response 000114 71234 Value 14 71234 000114 71235 Value 14 71235 000114 71234 Value 14 71234 REMOTE OPERATION 5 11 P7 High speed continuous pressure measurement in selected engineering units Action Continuously sample and send pressure measurement values using temperature measurement interval specified by the current value of PS P7 automatically performs the following sequence 1 Initially measure temperature period Measure pressure period 3 Calculate temperature compensated pressure using last temperature period measurement 4 Send pressure value 5 Do steps 2 4 the number of times specified by PS then measure temperature period 6 Repeat steps 2 5 until commanded to stop Typical command 0100P7 Typical response 000114 71234 Value 14 71234 000114 71235 Value 14 71235 000114 71234 Value 14 71234 Note P7 allows you to maximize the pressure sampling rate by taking temperature measurements at the interval specified by the PS command Each subsequent pressure value is temperature compensated using the currently stored temperature value You can take a single initial temperature measurement or you can take periodic temperature measurements at the interval you select with the PS command Please refer to the PS command for more information REMOTE OPERATION 5 12 PS Q2 Set or read
49. e function and the OP parameter USER INTERFACE 4 8 5 Remote Operation 5 1 Local vs RS 232 Operation The Model 735 745 can be operated either as a stand alone unit or as part of a computer based data acquisition system via its RS 232 communications port Virtually all of the functionality of the Model 735 745 is available via the RS 232 port Some of the unit s more specialized features can only be configured via the RS 232 port No special configuration is required to access the Model 735 745 via the RS 232 port Simply connect its industry standard RS 232 port to the RS 232 port of your host device set your host device to the proper baud rate and serial protocol and you are ready to communicate with the Model 735 745 The Model 735 745 RS 232 port is directly compatible with that of the PC Any standard male to female 9 pin serial cable can be used to make the necessary connections A serial cable Paroscientific PN 6409 003 is supplied with your Model 735 745 WARNING Do not attempt to simultaneously access the Model 735 745 through the RS 232 port and the configuration menu Doing so may cause serial commands or configuration menu selections to be ignored 5 2 Digiquartz Software Paroscientific provides several software programs that simplify common measurement and configuration tasks These programs can be found on the Digiquartz CD Library which is provided with the Model 735 745 The latest versions
50. e measurement data When US 0 no engineering units label is appended Examples 000114 71234 Pressure measurement US 0 000114 71234psia Pressure measurement US 1 000121 123 Temp measurement US 0 000121 123C Temp measurement US 1 When US 1 a pressure unit label is appended to pressure measurement values according to the value of UN UN value Label 0 Defined by UM 1 psia psig or psid 2 hPa 3 bar 4 kPa 5 MPa 6 inHg 7 mmHg 8 mH20 When US 1 a temperature unit label is appended to temperature measurement values according to the value of TU REMOTE OPERATION TU value Label 0 C 1 F Range Oorl Default 0 Typical set command Typical set response 0001US 1 Typical read command 0100US Typical read response 0001US 1 0100EW 0100US 1 5 25 SU Set or read the underscore separator parameter value Action When SU 1 an underscore separates the measurement data from the address header and the optional engineering units suffix When SU 0 no underscore separators appear Examples 000114 71234 SU 0 0001_14 71234 SU 1 0001_14 71234 psia SU 1 US 1 Range Oorl Default 0 Typical set command 0100EW 0100SU 1 Typical set response 0001SU 1 Typical read command 0100SU Typical read response 0001SU 1 ZI Set or read the taring indication parameter value Action When ZI 1 a T is appended to pressure measu
51. e purpose of this is to reduce the chance of changing a parameter value by mistake Parameter set commands will be ignored unless they are preceded with an EW command See paragraph 5 7 2 1 for more information about the EW command The following is an example of a parameter set command preceded with the EW enable write command For this example the UN pressure unit parameter will be set to a value of 1 Command 0100EW 0100UN 1CrLf Response 0001UN 1CrLf All other writable parameters are set in the same way Some parameters are read only and cannot be set READING PARAMETER VALUES All parameters can be read without preceding the command with an EW enable write command The following is an example of a parameter read command For this example the UN pressure unit parameter will be read Command 0100UNCrLf Response 0001UN 1CrLf CAUTION Repeatedly setting or reading parameter values may temporarily prevent the display from being updated REMOTE OPERATION 5 7 5 7 Command Reference 5 7 1 Measurement Commands The following commands are used to initiate measurements and to control measurement integration time For additional commands associated with Nano Resolution please refer to Section 6 5 7 1 1 Single Measurement Commands The following commands are used to initiate single measurements They return the resulting measurement value as soon as it is available P1 P3 Sample and send one
52. em one by one in a particular order Refer to paragraph 5 7 for detailed measurement command descriptions 7 4 Engineering Units Pressure values can be expressed in the following engineering units Refer to the UN command in paragraph 5 7 2 4 for details e psi hPa mbar bar kPa MPa in Hg mm Hg Torr m H20 User defined pressure units Temperature values can be expressed in the following units Refer to the TU command in paragraph 5 7 2 4 for details e C e F 7 5 Tare Function You can configure the Model 735 745 to subtract a value from each subsequent pressure measurement This process is referred to as taring You can tare subsequent pressure measurements to the current pressure value or to any value you specify Taring can be enabled and disabled through the configuration menu or by serial command An indicator on the display and or a special character in the RS 232 measurement data indicates when taring is in effect Refer to paragraphs 5 7 2 5 and 5 7 2 6 for details PRESSURE MEASUREMENT CONCEPTS 74 7 6 Resolution Integration Time and Sampling Rate 7 6 1 Definitions RESOLUTION Resolution is defined as the smallest change in measured quantity that can be detected INTEGRATION TIME Integration time is defined as the length of time that a Digiquartz pressure transducer output signal is sampled to produce a single measurement value SAMPLING RATE Sampling rate is defined as the number o
53. er entry screen UP ARROW increments the data value ENTER KEY e When in the configuration menus pressing ENTER selects the displayed menu item e When in a parameter entry screen ENTER accepts the displayed parameter value 4 1 4 Configuration Menu Options The Configuration Menu allows you to configure the Model 735 745 according to your application Refer to the Menu Quick Reference card or the menu tree in Section 20 4 1 4 1 Tare Menu CURRENT VALUE Displays the current tare value This is the value that is subtracted from pressure measurements when tare is on TARE Turns tare on When tare is on the current tare value is subtracted from pressure measurements When Tare is selected the pressure at that time becomes the current tare value If tare is already on when this option is selected tare remains on and the pressure at that time becomes the new current tare value When tare is on a T is displayed to the left of the pressure value to indicate that it is a tared pressure value TARE OFF Turns tare off When tare is off the actual measured pressure value is displayed USER INTERFACE 4 3 4 1 4 2 Units Menu PRESSURE UNITS Selects the pressure unit The following options are available e psi hPa bar kPa MPa inHg mmHg mH20 User defined pressure unit The user defined pressure unit can be selected via the configuration menu but must be configured via RS 232 Refer to Section 5 for detail
54. es 6 2 MD Serial data mode cc eee e cence ene ene ene ssn 5 18 MN Model number cece cece cence ceeeeeeeeeeeneneenes 5 29 OP Overpressure alarm setpoint 0 5 24 COMMAND AND PARAMETER REFERENCE 21 1 PARAMETERS CONTINUED PAGE PA PF PI PL Pressure adder oerein ea aa ai 5 32 Full scale pressure iii 5 29 Pressure integration time ene ene ene eneenenes 5 16 Setpoint for overpressure display indication 5 31 Pressure multiplier ccceceeceeee ene eeeeeeneenaenas 5 33 Pressure transducer type ene eneeneenens 5 29 Pressure resolution cece cee ce Li 5 17 Temperature measurement interval for P7 command 5 13 Serial number ccc ece cee ce eee e eset ene eeeeneenees 5 28 Data separation character enable disable 5 26 Td Coefficiente ai 5 34 T2 coeficient Li An 5 34 TI COCHMICIONE nel 5 34 TA COCMICIENE i iii lara apenas eee eee 5 34 TS coefficienti ii ia Lala 5 34 Timebase correction factor 0 5 33 Temperature integration time eee ee ees 5 16 Temperature resolution bb 5 17 Temperature unit C F L eee e cence eens eneees 5 21 UO coefficienti purea 5 34 User defined unit factor c cece cee eere essre 5 21 Stored text to display on line 2
55. esponse 0001DP 6 Typical read command 0100DP Typical read response 0001DP 6 Set the text to be displayed on the second line when the External Text display option is selected from the Configuration Menu Use DT when the Model 735 745 is to be controlled by an RS 232 serial host and the text must be updated frequently Action DT allows a serial host such as a PC to send text to be displayed on the bottom line The text sent using DT is not stored by the Model 735 745 it is simply transferred to its display DT cannot be queried and it is not necessary to precede DT with an EW command The text is lost when the Model 735 745 is powered off Range 16 characters maximum Any characters in the range of ASCII 32 to ASICC 127 are legal Typical set command 0100DT This is my text Typical set response 0001DT This is my text REMOTE OPERATION 5 30 PL UL Read the overpressure indication setpoint This setpoint is used to determine the pressure at which the overpressure indication is displayed PL is a factory set read only command Action When the Model 735 745 measures a pressure greater than the value of PL an overpressure indication is displayed Typical read command 0100PL Typical read response 0001PL 120 0000 Note PL is typically factory set to the overpressure limit as specified in the Specification Control Drawing for the Digiquartz transducer Set or read the text to be displayed on the second l
56. f measurements that can be taken in a given period of time 7 6 2 Interdependencies Resolution integration time and sampling rate are interdependent This is due to the method by which the Model 735 745 measures the outputs from the Digiquartz pressure transducer The integration time determines the resolution of the measurement Longer integration times increase resolution but reduce the sampling rate Conversely shorter integration times decrease resolution but increase the sampling rate Another factor that influences sampling rate is the serial baud rate For short integration times faster baud rates enable faster sampling As integration times increase the benefit of faster baud rates quickly diminishes Baud rate has no effect on integration time and therefore has no effect on resolution Tables 1 2 and 3 illustrate the relationship between integration time resolution and sampling rate for the P2 P4 and P7 commands at common baud rates PRESSURE MEASUREMENT CONCEPTS 7 5 P2 Command Continuous Pressure Period Output PR PI Resolution Integration 9600 baud 19200 baud ppm Time Hz s Hz 9 N A 1 678 168 0 001 73 53 0 014 147 06 0 007 1 3 242 203 0 003 68 49 0 015 136 24 0 007 3 8 80 734 0 008 68 49 0 015 110 62 0 009 4 11 60 551 0 011 68 49 0 015 83 89 0 012 6 17 40 367 0 017 56 56 0 018 56 56 0 01
57. fer to the MD command in paragraph 5 7 2 3 Increase the baud rate Refer to paragraph 4 1 4 4 Use the continuous pressure period command P2 and post process data to convert to pressure Refer to paragraph 7 8 for detailed information about converting period measurements into pressure values Networking The Model 735 745 supports RS 232 serial loop networking Networking allows you to communicate with up to 98 Digiquartz Intelligent devices from a single RS 232 serial host REMOTE OPERATION 5 36 5 9 1 Networking Basics When setting up a network the following points must be observed e If your network includes older Intelligent transmitters that support RS 232 only set the older devices to PT N to assure compatibility with the Model 735 745 e Verify proper operation of each Intelligent device before installing it in a network e Set all Intelligent devices to the same baud rate before installing them in a network e Each Intelligent device on the network needs to be set to a unique ID 5 9 2 RS 232 Loop Networking Refer to Figure 4 In an RS 232 serial loop network the transmit output of the RS 232 host is connected to the receive input of the first device in the loop The transmit output of the first device is connected to the receive input of the next device The remaining devices are connected similarly with their receive input connected to the transmit output of the previous device and their transmit output c
58. h of 16 characters MN is a read only command Typical read command 0100MN Typical read response 0001MN 745 15A Read the full scale pressure value Action The PF parameter contains the full scale pressure value in the current pressure units If the units are changed the value of PF is scaled accordingly PF is a read only command Typical read command 0100PF Typical read response 0001PF 30 00000 Read the pressure transducer type Action The PO parameter contains the pressure transducer type PO is a read only command PO value Transducer type 0 Absolute l Gauge 2 Differential Typical read command 0100PO Typical read response 0001PO 0 REMOTE OPERATION 5 29 5 7 2 8 Display Data Configuration Commands The Display Configuration commands allow you to alter the information shown on the display They also control the display of the optional Model 715 Remote Display DP DT Set or read the maximum number of decimal places in the displayed pressure value Action DP sets the maximum number of decimal places in the displayed pressure value Fewer decimal places will be displayed if the pressure resolution and or pressure unit will not provide the specified number of decimal places When DP is set to 6 the maximum number of decimal places is always displayed according to current pressure resolution Range 0 to6 Default 6 Typical set command 0100EW 0100DP 6 Typical set r
59. icated on the Digiquartz transducer The following example assumes serial number 1234567 Typical set command 0100EZ 0100SN 1234567 Typical set response 0001SN 1234567 At this point your Model 735 should be fully configured and should be displaying correct pressure measurement values If the displayed values are not correct refer to Section 13 for troubleshooting tips Refer to Section 4 for information about configuring your Model 735 according to your application 3 3 Applying Pressure Now that you have your Model 735 745 up and running you are ready to connect your pressure source to the pressure port If you are using a Model 745 you will connect your pressure source to the pressure port s located on its rear panel If you are using a Model 735 your pressure source will be connected directly to the pressure port of the external Digiquartz pressure transducer ABSOLUTE UNITS Units equipped with absolute pressure transducers have a single pressure port QUICK START 3 5 GAUGE UNITS Units equipped with gauge pressure transducers have two pressure ports Pressure should only be applied to the positive pressure port The negative pressure port must remain vented to atmospheric pressure WARNING Consult the Model 745 or Digiquartz pressure transducer SCD for proper pressure fitting tightening torque Do not apply excessive torque or permanent damage to the pressure fitting may result WARNING
60. il commanded to stop Typical command 0100Q4 Typical response 000122 345 Value 22 345 000122 346 Value 22 346 000122 345 Value 22 345 Note The Q4 command will temporarily prevent the front panel display from being updated 5 7 2 Configuration Commands 5 7 2 1 Enable Write Command When setting virtually all parameter values you must precede the parameter set command with an EW enable write command Parameter set commands will be ignored unless they are preceded with an EW command EW _ Enables the next parameter set command to write a new value into non volatile memory You can issue EW as a separate command by terminating it with a carriage return line feed or you can string the EW and parameter set commands together as shown below Typical syntax 0100EW 0100TR 800 Alternate syntax 0100EW 0100TR 800 5 7 2 2 Measurement Integration Time Commands The Model 735 745 supports two measurement integration modes time based and period based Time based integration samples the transducer pressure and temperature signals for a specified time and period based integration samples the signals for a specified number of periods of the REMOTE OPERATION 5 14 measured signal See paragraph 7 6 for information regarding the relationships between integration time resolution and sampling rate The desired integration mode is automatically selected depending on which integration time set command is issued For
61. ine when the Stored Text display option is selected from the Configuration Menu Action UL defines the text to be displayed on the bottom line The value of UL is stored in non volatile memory and will therefore be retained even if power is lost Range 11 characters maximum Any characters in the range of ASCII 32 to ASCII 127 are legal Default 11 space characters Typical set command 0100EW 0100UL My label Typical set response 0001UL My label Typical read command 0100UL Typical read response 0001UL My label CAUTION Do not use UL if it is necessary to update the displayed text often use the External Text display option and the DT command instead The nonvolatile memory used to store the text data can be written approximately 100 000 times excessive use of UL will eventually result in the inability to change its value REMOTE OPERATION 5 31 5 7 2 9 Calibration Commands The calibration commands set and read several parameters that directly affect the measurement accuracy of the device Refer to Section 10 for more information regarding the use of the calibration parameters CAUTION Calibration values should be modified only when absolutely necessary and then with extreme caution Calibration adjustments should only be performed by a qualified metrology lab PA and PM are used in the following formula to calculate final output pressure Padjusted PM P na PA Where P Pressure cal
62. ion in reference crystal resonant frequency TC is a read only command Typical read command 0100TC Typical read response 0001TC 6666667 REMOTE OPERATION 5 33 Set or read the calibration coefficients See paragraph 7 8 and Section 10 for more information about calibration and calibration coefficients Default Device specific Typical set command 0100EW 0100C1 228 1234 Typical set response 0001C1 228 1234 Typical read command 0100C1 Typical read response 0001C1 228 1234 5 7 2 10 Diagnostic Commands In the unlikely event of a hardware failure the diagnostic commands can assist in the troubleshooting process CS Read the number of unused bytes on the stack since power up Action CS is read only it cannot be set It can be used to determine whether a stack overflow may have occurred Typical read command 0100CS Typical read response 0001CS 8 REMOTE OPERATION 5 34 CX Check timebase crystal frequency Action Puts the timebase frequency divided by 480 on the Tare Output I O line The timebase signal is removed from the Tare Output I O line when the next valid command is received CX cannot be queried The CX set command does not produce a response Typical set command 0100CX Typical set response No response 5 7 2 11 Global Commands Under certain circumstances it may be desirable to send a single command to multiple units on a serial loop network The ID 99 has been reserved for such global add
63. ions Digiquartz Intelligent Instruments are precision devices and as such they should be operated with a certain degree of care to ensure maximum performance WARNING It is recommended that the input pressure not exceed the specified limit Calibration can be affected if this limit is exceeded and permanent damage can result if the unit is sufficiently overpressured WARNING Excessive mechanical shock may cause irreparable damage Do not drop a Digiquartz Intelligent Instrument or allow tools or other hard objects to fall on the unit or its pressure port INTRODUCTION i 2 Getting Familiar 2 1 Physical Inspection You should have received the following items with your Model 735 745 purchase e Model 735 or Model 745 User s manual RS 232 serial cable 110V or 220V AC adapter 4 AA alkaline batteries Model 735 745 Menu Quick Reference Digiquartz CD Library Specification Control Drawing SCD for the Model 735 or 745 Specification Control Drawing SCD for the Digiquartz pressure transducer Model 735 only 2 2 Product Features and Configurations Performance and feature specifications are subject to change Please refer to the Specification Control Drawing SCD that was delivered with your unit PERFORMANCE MODEL 745 Resolution Better than 0 0001 full scale Accuracy Better than 0 008 full scale accuracy for all ranges except 0 08 hPa for barometric range Model 745 16B 0 02 full sca
64. l 4 1 1 Display The Model 735 745 features a 2 line 16 character alphanumeric LCD display 4 1 2 Operating Modes The Model 735 745 operates in one of two modes Pressure Display Mode or Configuration Menu Mode PRESSURE DISPLAY MODE At power up the Model 735 745 will be in Pressure Display Mode When in Pressure Display Mode the first line displays the following information e Pressure value e Pressure unit e Tare indicator e Pressure value update indicator blinking dot between the pressure value and pressure unit The second line can display one of the following e Pressure bar graph Digiquartz pressure transducer internal temperature Pressure rate of change Text stored within the Model 735 745 External text sent to the Model 735 745 via the RS 232 port No information The second line can also display an overpressure warning if the measured pressure exceeds the limits of the Digiquartz pressure transducer This feature is not available in the pressure rate of change and external text display modes USER INTERFACE 4 1 CONFIGURATION MENU MODE Configuration Menu Mode is accessed by pressing the MENU key while in Pressure Display Mode The most common functions of the Model 735 745 can be configured through the configuration menus Less frequently used functions are accessed through the RS 232 port See Section 5 for details The configuration menus are organized in a hierarchical fashion as shown in Section 20 The
65. le for 30 000 and 40 000 psi units PERFORMANCE MODEL 735 Per external transducer Specification Control Drawing SCD GETTING FAMILIAR 2 1 RANGES Model 745 e 19 absolute pressure ranges 0 15 psia 0 1 MPa to 0 40 000 psia 276 MPa e 6 gauge pressure ranges 0 15 psig 0 1 MPa to 0 200 psig 1 38 MPa Model 735 e Supports all Paroscientific frequency output pressure sensors with temperature signal outputs FEATURES e Intuitive front panel menu system e Two line display with menu selectable functions Taring Engineering units Pressure bar graph Sensor temperature Password protection Rate of pressure change Resolution and sampling speed Adjustable number of display digits User choice of stored or external text Optional part per billion resolution Nano resolution Rack or panel mount capability Enhanced RS 232 command set 110V or 220V AC adapter power Multiple remote display capability Free configuration and logging software 20 hours battery operation in standard resolution mode 4 AA size alkaline QUALITY AND STANDARDS e CE marked e NIST traceable 2 3 Physical Description The Model 735 and 745 are nearly identical in function and appearance The main difference is that the Model 735 is used with an external GETTING FAMILIAR 2 2 Digiquartz pressure transducer while the Model 745 has an internal Digiquartz pressure transducer The Model 735 745 display pressure measurement values and related information
66. mpling applications Period measurements can only be accessed via the RS 232 port When a period measurement is made the following sequence occurs e The pressure or temperature signal period is measured e The period value is output Refer to paragraph 5 7 for detailed measurement command descriptions 7 3 Sampling Types Measurement data can be sampled via the RS 232 port by the following methods Single measurement Continuous measurement High speed continuous measurement Sample and hold measurement SINGLE MEASUREMENT SAMPLING Single measurement sampling commands output a single measurement value each time the command is received CONTINUOUS MEASUREMENT SAMPLING Continuous measurement sampling commands repeatedly output measurement data until commanded to stop HIGH SPEED CONTINUOUS MEASUREMENT SAMPLING Similar to regular continuous measurement commands but internal transducer temperature measurements are taken only occasionally This type of sampling is useful when sampling rates must be as high as possible and is particularly effective when internal transducer temperature is not expected to change significantly PRESSURE MEASUREMENT CONCEPTS 7 3 SAMPLE AND HOLD MEASUREMENT SAMPLING Similar to single measurement sampling but the measurement value is not output until a separate command is sent This type of sampling is useful when you need to simultaneously trigger measurements from multiple units and then read th
67. nits OP should be set to the full scale pressure indicated on the Digiquartz transducer The following example assumes a 45 psi transducer Typical set command 0100EW 01000P 45 Typical set response 00010P 45 00000 QUICK START 3 2 e Set the transducer coefficient values The following parameters must be set to the corresponding values on the Calibration Coefficients data sheet that was delivered with your Digiquartz transducer U0 Y1 Y2 Y3 C1 C2 C3 D1 D2 T1 T2 T3 T4 and T5 You must set all calibration parameters to the exact values listed on the Calibration Coefficients data sheet CAUTION Setting calibration coefficients to incorrect values will result in incorrect pressure measurement values The following example shows how to set the UO coefficient to a typical value Other coefficients are set in a similar manner Refer to paragraph 5 7 2 9 for more information Typical set command 0100EW 0100U0 5 8605 13 Typical set response 0001U0 5 8605 13 e Set the transducer model number MN should be set to the model number indicated on the Digiquartz pressure transducer The following example assumes a model 245A transducer Typical set command 0100EZ 0100MN 245A Typical set response 0001MN 245A e Set the transducer full scale pressure value Set PF to the full scale pressure value indicated on the Digiquartz pressure transducer PF is set in the current pressure units We recommend
68. ns product modification zero adjustments recalibration and service analysis charges This Extended Limited Warranty is a supplement to Paroscientific Inc s Terms and Conditions of Sale Shipping charges are the responsibility of the customer Months From Shipment Discount From List Price 0 24 100 25 36 75 37 48 50 49 60 25 CONDITIONS e The warranty period is from the date of shipment from Paroscientific to date of receipt at Paroscientific e The customer must authorize the repair or replacement of the warranty claim within 45 days of notification by our Service Department e No exceptions to the discount schedule or terms of this policy are allowed e This warranty does not apply to units broken due to overpressure or excessive shock e Warranty returned units become the property of Paroscientific upon replacement WARRANTY 11 1 e All barometers also have a three year limited warranty on long term stability Years 4 amp 5 are covered by the above schedule WARRANTY 11 2 12 Service and Support Technical support is available via our web site www paroscientific com and our sales and application engineers Product technical information application notes software and product manuals are available on our web site Please check the troubleshooting section of this manual if you are having problems with your instrument If you need technical assistance contact our s
69. nts 10 3 Calibrating Other Instruments The Digiquartz Model 745 High Accuracy Pressure Standard can be used to calibrate other pressure instruments Its 0 008 of full scale accuracy and 0 0001 resolution make the Model 745 ideal for laboratory and metrology applications When calibrating another pressure instrument apply the same pressure to the Model 745 and the test instrument Take the difference in pressure readings between the test instrument and the Model 745 Apply the difference as a correction to the test instrument For details regarding the calibration of a third party pressure instrument please review its user documentation or consult the manufacturer CALIBRATION 10 3 11 Warranty Paroscientific highly values our customers Our Quality Assurance System provides consistency in our products and processes from design and development through production calibration test and servicing Our quality system and commitment to excellence ensure customers of outstanding products and services As a result we offer a one year warranty on all instrumentation systems and a full five year limited warranty on all Digiquartz transducers that is unmatched in the industry This policy applies to all Digiquartz transducers manufactured by Paroscientific and includes the repair and or replacement of parts that are required to maintain the unit to the as purchased configuration Excluded from this policy are the following conversio
70. of significant digits used to report period pressure and temperature measurement values The XN command overrides the default numeric format NANO RESOLUTION FEATURES amp FUNCTIONS 6 6 XN Set or read the number of significant digits displayed and or output Range 0 13 Default 0 Typical set command 0100EW 0100XN 10 Typical set response 0001XN 10 Typical read command 0100XN Typical read response 0001XN 10 When XN is set to 0 the default numeric formats are used When non zero XN specifies the number of significant digits used to report period pressure and temperature measurement values With the exception of the total number of digits all default format characteristics apply The integer portion is never expressed with fewer digits than required regardless of the value of XN The fractional portion is rounded or padded with zeros as required to fit the specified format The XN command works with Standard IIR and FIR resolution modes Note The Model 735 745 can display a maximum of 10 significant digits Values with greater than 10 digits will be rounded as required NANO RESOLUTION FEATURES amp FUNCTIONS 6 7 7 Pressure Measurement Concepts 7 1 Measurement Basics At the heart of all Digiquartz Intelligent Instruments is a precision Digiquartz pressure transducer The outputs from a Digiquartz pressure transducer are two square wave signals whose period is proportional to applied pressure and intern
71. onnected to the receive input of the next device The transmit output of the last device is connected to the receive input of the RS 232 host The host sends commands to the first device in the loop If a command is addressed to that device the command is carried out if not the command is resent to the next device Globally addressed commands are carried out by each device and are also resent to the next device When a device responds to a command the response is addressed to the host and is therefore resent by each device that receives it until it eventually makes it way to the serial host REMOTE OPERATION 5 37 TRANSMIT RECEIVE TRANSMIT ID 01 __ RECEIVE TRANSMIT ID 02 m RECEIVE TRANSMIT ID C INTELLIGENT DEVICE INTELLIGENT DEVICE 2 INTELLIGENT DEVICE 3 RECENE REMOTE OPERATION RS 232 ERIAL HOST Figure 4 Serial loop network block diagram Keep these points in mind when designing an RS 232 serial loop network As previously described each device resends any command or response that is addressed to another device Since each device considers resending to be a higher priority than sending its own response it is possible that a device can spend all its time resending and never have an opportunity to send its own response This occurs only when one or more upstream devices are continuously transmitting To prevent this situation e Operate your
72. or the latest manual revision 1 1 Latest features With firmware revision D1 06 or later it is now possible to achieve parts per billion resolution nano resolution as opposed to parts per million resolution in standard mode This feature can be easily enabled disabled via software commands Please refer to Section 6 for additional information on this new feature 1 2 Conventions The following conventions are used throughout this manual Digiquartz Intelligent Instrument A Digiquartz Model 735 Intelligent Display or Model 745 Laboratory Standard Digiquartz Intelligent Transmitter Any Digiquartz Series 1000 6000 or 9000 Pressure Transmitter or Intelligent Depth Sensor Digiquartz Intelligent Device Any Digiquartz Intelligent Instrument or Transmitter Digiquartz Pressure Transducer Any Digiquartz pressure transducer with frequency outputs CAUTION is used to draw your attention to a situation that may result in an undesirable outcome but will not damage the unit WARNING is used to draw your attention to a situation that may result in permanent damage to the unit or will void the warranty INTRODUCTION Mi DANGER is used to draw your attention to a situation that may result in injury Commands and parameters are shown in bold type Example PI and TI are commands that set the integration time in increments of 0 01 second 1 3 Warnings and Safety Precaut
73. raphs 4 1 4 2 and 5 7 2 4 4 How do I change the pressure sampling rate Refer to paragraphs 4 1 4 4 and 5 7 2 2 5 How dol talk to the instrument via the RS 232 interface Refer to Section 5 6 What are the RS 232 commands Refer to paragraph 5 7 and Section 21 7 How do I tare the unit Refer to paragraphs 4 1 4 1 and 5 7 2 5 8 How do I change the look of the display Refer to paragraphs 4 1 4 3 and 5 7 2 8 9 How do I change the RS 232 baud rate Refer to the Baud Rate menu option in paragraph 4 1 4 4 10 How do I prevent access to the instrument via the front panel Refer to the Password menu option in paragraph 4 1 4 4 11 How do I change the number of digits in the pressure display Refer to the Decimal Digits menu option in paragraph 4 1 4 4 12 How do I change the unit ID Refer to the Unit ID menu option in paragraph 4 1 4 4 HOW DOI 19 1 20 Menu Tree Reference 1 Tare Menu 1 Current Value A Tare 3 Tare Off 2 Units Menu 1 Pressure 4 Temp Units 3 Display Menu 1 Decimal Digits 4 Line 2 Display 4 AuxMenu 1 Sampling Time 4 Unitid 3 Password 4 Version 5 Baud Rate MENU TREE REFERENCE III Sat CS D SED S id Lat D DI FECE che User Defined C Bar Graph Sensor Temp Pressure Rate Stored Ted Bemal Tet No Line 19200 9600 4800 2400 1200 600 300 20 1 21 Command and Parameter Reference COMMANDS PAGE CS Checkstacks tuoi lalla 5 34 CX
74. rcury or Torr gm cm mbar Pascal 1 0 gm cm in Hg mm Hg hPa Pa Meters H2O 1 1 422334 2 895903 73 5592 100 0000 98 06650 9806 650 psi 7030696 1 2 036021 51 71493 70 30696 68 94757 6894 757 Inches of Hg 3453155 4911541 1 25 40000 34 53155 33 86388 3386 388 cae Hg 01359510 01933678 03937008 1 1 359510 1 333224 133 3224 Gram em 01000000 01422334 02895903 7355592 1 9806650 98 06650 Millibars 01019716 01450377 02952999 75000617 1 019716 1 100 0000 Newton m 1 019716 1 450377 2 952999 7 500617 01019716 01000000 1 X10 X10 X10 X10 i PRESSURE UNIT CONVERSION TABLE 15 1 16 Glossary The following is a list of definitions related to the Model 735 745 Digiquartz Intelligent Instrument A Digiquartz Model 735 Intelligent Display or Model 745 Laboratory Standard Digiquartz Intelligent Transmitter Any Digiquartz Series 1000 6000 or 9000 Pressure Transmitter or Intelligent Depth Sensor Digiquartz Intelligent Device Any Digiquartz Intelligent Instrument or Transmitter Digiquartz Pressure Transducer Any Digiquartz pressure transducer with frequency outputs Integration Time The time over which the Digiquartz pressure transducer output signals are measured Also referred to as sampling time Pressure Signal The Digiquartz pressure transducer output whose frequency is related to applied pressure Resolution The smallest change in measured quan
75. rd pressure units 0 selects a user defined unit whose conversion factor is specified by the UF command UN also sets the units of the pressure data displayed by an optional Model 715 display Range 0 to8 UN Pressure psi multiplied value units by 0 User defined pressure unit Value of UF 1 psi 1 0000000 2 hPa mbar 68 94757 3 bar 0 06894757 4 kPa 6 894757 5 MPa 0 00689476 6 in Hg 2 036021 7 mm Hg Torr 51 71493 8 m HLO 0 7030696 Default 1 Typical set command Typical set response Typical read command Typical read response 0100EW 0100UN 2 0001UN 2 0100UN 0001UN 2 5 20 REMOTE OPERATION UF TU Set or read the user defined pressure engineering units conversion factor Action When UN 0 calculated pressure values psi are multiplied by the value of UF before being output thus scaling the pressure values in the desired user defined pressure units Range 9999999 to 9999999 Default 1 0000000 Typical set command 0100EW 0100UF 2 Typical set response 0001UF 2 Typical read command 0100UF Typical read response 0001UF 2 000000 Set or read the temperature engineering units Action Specifies the temperature units for Q3 Q4 Q5 and displayed temperature data Range 0 C F Default 0 Typical set command 0100EW 0100TU 1 Typical set response 0001TU 1 Typical read command 0100TU Typical read response 0001TU 1 Note Temperature
76. re used to initiate and send single sample and hold measurements Measurement values are held until the next command is received If the next command is a DB command the measurement value is sent if it is any other command the measurement value is lost If a DB command is received before the measurement command is complete the measurement value will be sent as soon as it is available CAUTION Sample and hold commands will temporarily prevent the front panel display from being updated until the DB command is received or the sample and hold command is cancelled by the next valid command REMOTE OPERATION 5 9 P5 P6 Q5 Q6 DB Sample and hold one pressure measurement in selected engineering units Action Measure temperature period measure pressure period calculate temperature compensated pressure save pressure value and await DB command Typical command 0100P5 Typical response No response until DB command is received Sample and hold one pressure period measurement in units of microseconds Action Measure pressure period save pressure period value and await DB command Typical command 0100P6 Typical response No response until DB command is received Sample and hold one temperature measurement in selected engineering units Action Measure temperature period calculate temperature save temperature value and await DB command Typical command 0100Q5 Typical response No response until D
77. rement values when taring is in effect When ZI 0 no taring indication appears whether taring is in effect or not Examples 000114 71234 ZI 0 000114 71234T ZI 1 0001_14 71234T ZI 1 SU 1 000114 71234Tpsia ZI 1 US 1 0001_14 71234T psia ZI 1 US 1 SU 1 Range Oorl Default 0 Typical set command 0100EW 0100ZI 1 Typical set response 0001ZI 1 Typical read command 0100ZI Typical read response 0001ZI 1 REMOTE OPERATION 5 26 DL Set or read the fixed field data format parameter Action When DL 1 measurement data is formatted in a fixed field format When DL 0 measurement data is given in the standard format The fixed field format is specified as follows A AAASDDDDDDDDDD where the asterisk character A destination and source address characters S sign of pressure data either or D numeric representation of pressure data either digits or a decimal point Examples 000114 71234 Pressure DO 0 0001 14 7123400 Pressure DO 1 000121 123 Temperature DO 0 0001 21 1230000 Temperature DO 1 Range Oorl Default 0 Typical set command 0100EW 0100DL 1 Typical set response 0001DL 1 Typical read command 0100DL Typical read response 0001DL 1 Note The format specification and examples shown above assume that the other formatting commands are disabled If other formatting commands are used in combination with DL a fixed field format will still resul
78. ressing When a Model 735 745 receives a legal command addressed to ID 99 it reacts to that command regardless of its assigned ID value When the Model 735 745 receives a global command via RS 232 it retransmits the global command before acting on it This ensures that all units on a serial loop will receive the global command Eventually the global command is retransmitted by the last unit in the serial loop and is received by the serial host The serial host must be able to disregard the retransmitted command Global addressing is often used with sample and hold measurement commands to synchronize measurements from multiple devices The sample and hold measurement commands are P5 and P6 Q5 and Q6 REMOTE OPERATION 5 35 All sampling commands and certain other commands may be either individually or globally addressed P1 through P7 Q1 through Q6 DB VR EW The remaining commands should not be sent as global commands 5 8 High Speed Sampling Use one or more of the following techniques to increase the RS 232 sampling rate 5 9 Reduce integration time Refer to PI TI PR and TR commands in paragraph 5 7 2 2 Use PR and TR rather than PI and TI to control integration time PR and TR have approximately lms resolution compared to 10ms of PI and TI See paragraph 5 7 2 2 for details Use a continuous pressure measurement command such as P4 or P7 See paragraph 5 7 1 3 for details Turn off display data output Re
79. s TEMP UNITS Selects the internal sensor temperature unit The following options are available e C e F 4 1 4 3 Display Menu DECIMAL DIGITS Selects the number of significant digits used to display pressure measurement values Fewer significant digits will be displayed if the pressure resolution and or pressure unit will not provide the specified number of significant digits When the number of digits is set to 6 the maximum number of significant digits is always displayed LINE 2 DISPLAY Selects the information to be displayed on the second line The following options are available e Bar graph gives a graphic representation of the current pressure value as a percentage of full scale pressure e Sensor Temp displays the Digiquartz pressure transducer internal temperature USER INTERFACE 4 4 e Pressure Rate displays the pressure rate of change in the current pressure unit per second Pressure rate is calculated as the difference between adjacent pressure measurements divided by the measurement time interval Time interval accuracy is 10 milliseconds e Stored Text displays the text stored within the Model 735 745 The text is defined via the RS 232 port using the UL parameter Refer to paragraph 5 7 2 8 for more information e External Text displays the text sent via the RS 232 port using the DT command The text is not stored within the Model 735 745 and will be lost if the unit is turned off e No
80. se 0001PR 200 Note Whenever the value of PR is changed TR is automatically updated with the value of PR times 4 Set or read period based temperature measurement integration time Units None Range 1 to 65535 Default 952 Typical set command 0100EW 0100TR 800 Typical set response 0001TR 800 Typical read command 0100TR Typical read response 0001TR 800 Note Whenever the value of PR is changed TR is automatically updated with the value of PR times 4 Changing TR has no effect on PR TR should be set to the value as PR times 4 for optimum performance in most applications REMOTE OPERATION 5 17 5 7 2 3 Data Output Mode Command The following command controls whether pressure data is continuously output and whether display data are produced MD Setor read the data output mode Action MD configures the Model 735 745 for continuous serial pressure measurement output and or display data output whenever power is applied MD Display data Continuous serial value output pressure data output 0 OFF OFF 1 ON OFF 2 OFF ON 3 ON ON Once MD is set the specified data output mode will remain in effect until MD is set to a different value even through a power cycle Therefore the Model 735 745 will perform the specified data output function whenever power is applied Range 0 3 Default 1 Typical set command 0100EW 0100MD 1 Typical set response 0001MD 1 Typical read command
81. splay When these conditions occur DISPLAY DATA INTERRUPTED is displayed Normally the Model 735 745 resumes pressure value display when the condition is no longer present The following conditions will cause the Model 735 745 to display the DISPLAY DATA INTERRUPTED message An asterisk is sent to the RS 232 port but the terminating characters Cr Lf are never sent One of the following RS 232 commands is in effect P2 P5 P6 Q2 Q4 Q5 Q6 The integration time is increased substantially Parameter values are continuously set or queried via RS 232 MD is set to 0 or 2 via RS 232 When the aforementioned conditions are no longer present the Model 735 745 will resume pressure data display If none of the conditions are present and the unit continues to displays the DISPLAY DATA INTERRUPTED message the unit may be in need of service Refer to Section 12 for service and support information DISPLAY DATA INTERRUPTED MESSAGE 14 1 15 Pressure Unit Conversion Table To use this table e Determine original pressure unit and desired pressure unit e Using the table identify the appropriate pressure conversion factor e Multiply the original pressure value by the conversion factor to convert it to the desired pressure unit Desired Pressure Unit Original gt a Pressure Meters H2O psi Inches of mmofHg Gram cm Millibars Newton m Unit density me
82. sponse 0001XT 10 Typical read command 0100XT Typical read response 0001XT 10 NANO RESOLUTION FEATURES amp FUNCTIONS 6 5 6 5 Default Numeric Formats for IIR amp FIR Modes The default numeric formats used to report period pressure and temperature measurement values via the display and or RS 232 port are as follows where N the number of significant digits shown in the resolution tables Note The Model 735 745 can display a maximum of 10 significant digits Values with greater than 10 digits will be rounded as required PRESSURE The sensor full scale pressure defines the number of digits reserved for the integer portion of the pressure value For example a 1000 psi full scale unit would have 4 digits reserved but not necessarily used for the integer portion of the pressure value leaving N 4 digits for the fractional portion TEMPERATURE Three digits are reserved but not necessarily used for the integer portion of the temperature value leaving N 3 digits for the fractional portion Negative temperature values include a sign but the numeric format is otherwise unaffected PRESSURE PERIOD Two digits are used for the integer portion of the pressure period value leaving N 2 digits for the fractional portion TEMPERATURE PERIOD One digit is used for the integer portion of the pressure period value leaving N 1 digits for the fractional portion 6 6 Controlling the Numeric Format The XN command sets the number
83. ssrsssscecsssssossesonssossencnesence 5 1 5 1 Local vs RS 232 Operation xii 5 1 5 2 Digiquartz Softwat ridusse vela anne 5 1 5 2 1 Digiquartz Interactive 2 0 DQI 2 0 5 1 5 2 2 Digiquartz Assistant DQA n 5 2 5 2 3 Digiquartz Terminal DQT ceeeeereeeteees 5 2 5 3 Command and Response Basics 5 3 5 4 Command and Response Format 5 3 5 5 Establishing RS 232 Communications 5 5 5 6 Setting and Reading Parameter Values 5 7 5 7 Command Reference suerte ected 5 8 5 7 1 Measurement Commands i 5 8 5 7 1 1 Single Measurement Commands 5 8 5 7 1 2 Sample and Hold Measurement Commands 5 9 5 7 1 3 Continuous Measurement Commands 5 11 5 7 2 Configuration Commands e 5 14 5 7 2 1 Enable Write Command 5 14 5 7 2 2 Measurement Integration Time Commands 5 14 5 7 2 3 Data Output Mode Command 5 18 5 7 2 4 Engineering Units Commands 5 20 5 7 2 5 Tare and Overpressure Commands 5 21 5 7 2 6 Measurement Data Formatting Commands 5 24 5 7 2 7 Unit Identification Commands 5 28 5 7 2 8 Display Data Configuration Commands 5 30 5 7
84. sulting in erratic pressure measurements WIRING DIAGRAMS 18 2 SND 5 ID 2 ID N 98 MAX INTELLIGENT INTELLIGENT INTELLIGENT DEVICE DEVICE 2 DEVICE N Figure 7 Serial loop network wiring diagram Note Figure 7 is a generic diagram that is meant to illustrate the concept for all Digiquartz Intelligent Instruments Please note that the power connections on a Model 735 745 are located on a separate terminal block adjacent to the RS 232 connector WIRING DIAGRAMS 18 3 18 4 Model 715 Display The diagram in Figure 8 shows how to connect a Model 715 Remote Display to the Model 735 745 Use a shielded twisted pair cable designed for RS 485 communications and ensure that the DISPLAY and DISPLAY signal wires are twisted With the proper cable it is usually possible for the Model 735 745 to drive 4 000 feet of cable ae DISPLAY OUT 4 TX 4 RS 485 PORT DISPLAY OUT TX GND 21 GND MODEL 735 745 MODEL 715 DC POWER IO TERMINAL BLOCK TERMINAL BLOCK Figure 8 Model 735 745 to Model 715 wiring diagram WIRING DIAGRAMS 18 4 19 Howdol 1 How do I configure my instrument Refer to paragraph 4 1 4 and Section 5 2 How do I access the menu system Refer to paragraphs 4 1 1 4 1 2 4 1 3 and 4 1 4 3 How do I change the pressure or temperature unit Refer to parag
85. t but the format specification will vary slightly from the one described above REMOTE OPERATION 5 27 UM Set or read the user defined engineering units label parameter Action When UN 0 and US 1 the text value of UM is appended to pressure measurements Examples 000114 71234 UN 0 US 0 000114 71234user UN 0 US 1 UM user Range Any text up to four characters consisting of ASCII 32 to ASCII 127 Default user Typical set command 0100EW 0100UM test Typical set response 0001UM test Typical read command 0100UM Typical read response 0001UM test 5 7 2 7 Unit Identification Commands The Unit Identification commands read various device specific parameters These parameters are factory set and cannot be modified SN VR Read the serial number Action The SN parameter contains the device serial number SN is a read only command Typical read command 0100SN Typical read response 0001SN 12345 Read the firmware version number Action The VR parameter contains the device firmware version number VR is a read only command Typical read command 0100VR Typical read response 0001VR D1 02 REMOTE OPERATION 5 28 MN PF PO Read the model number Action The MN parameter contains the device model number as a text string The value of MN always contains 16 characters If the model number is less than 16 characters the string will be padded with trailing spaces to a lengt
86. ter used as a primary standard depends directly on the piston area and the value of local gravity Any apparent change of span in a Paroscientific transducer should be carefully checked to ascertain that the pressure is correctly applied and calculated with the correct piston area and gravity constant and that the piston is vertical We recommend recording several pressure points over the entire pressure range to establish any span error The Paroscientific calibration software program RECAL calculates the best span by a least squares fit optimization Please refer to the document entitled Recalibration of Paroscientific Transducers Doc 8140 001 at www paroscientific com for details regarding offset and span adjustment Calibration should only be performed by a skilled metrologist The PA and PM commands allow you to make zero and span adjustments Normally PA pressure adder is set to 0 0 and PM pressure multiplier is set to 1 0 Adjusted pressure is calculated using the following equation Padjusted PM P F PA Where P Pressure calculated using original calibration coefficients in the current pressure units PM the current value of PM PA the current value of PA Refer to paragraphs 5 7 2 9 and 7 8 for more information regarding PA and PM CALIBRATION 10 2 CAUTION PA and PM directly affect calibration Use extreme caution when modifying PA or PM Improper PA and or PM values will result in inaccurate pressure measureme
87. tity that can be resolved Sampling Rate The number of pressure measurements taken per a given time unit often expressed in Hertz Hz Sampling Time The time over which the Digiquartz pressure transducer output signals are measured Also referred to as integration time Temperature Signal The Digiquartz pressure transducer output whose frequency is proportional to internal sensor temperature GLOSSARY 16 1 17 Connector Diagrams All connector diagrams in this section are viewed from the mating side 17 1 Model 735 745 RS 232 Port Connector DB9 F Connection Not used RS 232 TX RS 232 RX Not used Ground Not used Not used Not used Not used CONCESSE CONNECTOR DIAGRAMS 17 1 17 2 PC RS 232 Port Connector Pin assignments are typical If in doubt consult the hardware manual that came with your PC DB9 M Pin Connection 1 Data Carrier detect DCD 2 RS 232 RX 3 RS 232 TX 4 Data Terminal Ready DTR 5 Ground 6 __ Data Set Ready DSR Request To Send RTS Clear To Send CTS Ring Indicator RI Sjo 17 3 Model 735 745 DC Power I O Terminal Block Contact Connection 1 Display Out 2 Display Out 3 Ground 4 Overpressure Output 5 Ground 6 6 to 25 VDC CONNECTOR DIAGRAMS 17 2 17 4 Mo
88. updated MODEL 735 745 DISPLAYS INCORRECT PRESSURE VALUES Check that the calibration coefficients are correct Digiquartz Interactive software can be used for this purpose The proper calibration coefficients are listed in the calibration data sheet that was provided with your Model 745 or Digiquartz pressure transducer If you are unable to locate the calibration data sheet contact Paroscientific for the calibration coefficients TROUBLESHOOTING 13 1 MODEL 735 745 DISPLAYS DISPLAY DATA INTERRUPTED Refer to Section 14 MODEL 735 745 PRODUCES ERRATIC PRESSURE MEASUREMENTS If you are powering multiple units from a common DC power supply you must run separate power and ground wires from each unit to the power supply Wire size should be 18 AWG minimum Transducer ground wire s should not be connected to the chassis ground terminal Refer to paragraph 18 1 MODEL 735 745 SECOND LINE DISPLAY DOES NOT UPDATE The Model 735 745 gives priority to RS 232 communications If you are repeatedly acquiring pressure data via RS 232 with the P3 command it is possible that the Model 735 745 will not have sufficient time to update the second line of the display This can be avoided by inserting a short delay between each P3 response and the next command The length of the required delay is dependant on baud rate The following table shows the minimum delay for each supported baud rate Baud Rate Delay ms
89. ure 3 Model 745 rear panel The Model 745 rear panel contains the following features Pressure port s AC adapter jack Power and I O terminal block RS 232 port Battery compartment Chassis grounding lug Please refer to paragraph 4 2 for detailed information about the Model 745 rear panel features GETTING FAMILIAR 2 5 3 Quick Start This section will help you to quickly set up the Model 735 745 and begin taking pressure measurements 3 1 Model 745 Step 1 Apply power to the Model 745 Refer to paragraph 4 2 1 for detailed information Step 2 Turn Model 745 on Press the ON OFF key to turn on the Model 745 After a short initialization the Model 745 will begin to display pressure measurement values Your Model 745 should now be displaying correct pressure measurement values If the displayed values are not correct refer to Section 13 for troubleshooting tips Refer to Section 4 for information about configuring your Model 745 according to your application 3 2 Model 735 Step 1 Connect an external Digiquartz pressure transducer to the Model 735 e Refer to paragraph 18 1 for detailed information Step 2 Apply power to the Model 735 e Refer to paragraph 4 2 1 for detailed information Step 3 Turn Model 735 on e Press the ON OFF key to turn on the Model 735 After a short initialization the Model 735 will begin to display pressure measurement values Note If the Model 735 has not yet been configured with
90. xtended period of time it is recommended that the batteries be removed WIRE INTERFACE The DC Power I O terminal block provides a means of wiring DC power to the Model 735 745 USER INTERFACE 4 7 4 2 2 Terminal Block Descriptions Terminal block s are provided for making wire connections to the Model 735 745 The terminal blocks can be unplugged from the unit to simplify wiring Refer to the pinout diagrams on the rear panel label when making connections DC POWER I O TERMINAL BLOCK The DC Power I O terminal block provides the following connections e DC power and power ground e Model 715 remote display signals e Overpressure output Refer to paragraph 17 3 for detailed information regarding the DC Power I O terminal block Refer to paragraph 5 7 2 5 for detailed information regarding the overpressure output TRANSDUCER INTERFACE TERMINAL BLOCK MODEL 735 ONLY The transducer interface terminal block provides the connections to the external Digiquartz pressure transducer Refer to paragraph 18 1 for detailed information regarding the transducer interface terminal block 4 3 Overpressure Alert The overpressure alert is an audible alarm that works in conjunction with the overpressure output It sounds whenever the displayed pressure exceeds a user selectable pressure setpoint The setpoint is controlled via RS 232 by the OP parameter Refer to paragraph 5 7 2 5 for detailed information regarding the overpressur

Model 735 Intelligent Display User`s Manual

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