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Manual - Lake Shore Cryotronics, Inc.

1. Range Resolution wi Filter Resolution w out Filter HST Probe 300 kG 0 001 kG 0 01 kG 30 kG 0 0001 kG 0 001 kG 3 kG 0 00001 kG 0 0001 kG 300 G 0 001 G 0 01 G HSE Probe 30 kG 0 0001 kG 0 001 kG 3 kG 0 00001 kG 0 0001 kG 300 G 0 001 G 0 01 G 30 G 0 0001 G 0 001 G UHS Probe 30 G 0 0001 G 0 001 G 3G 0 00001 G 0 0001 G 300 mG 0 001 mG 0 01 mG DC Accuracy 0 10 of reading 0 005 of range DC Temperature Coefficient 0 05 of reading 0 03 of range C AC RMS amp Peak Measurement AC Display Resolution 4 digits Range RMS Resolution Peak Resolution HST Probe 300 kG 0 01 kG 0 01 kG 30 kG 0 001 kG 0 001 kG 3kG 0 0001 kG 0 0001 kG 300 G 0 01 G HSE Probe 30 kG 0 001 kG 0 001 kG 3kG 0 0001 kG 0 0001 kG 300 G 0 01 G 0 01 G 30 G 0 001 G UHS Probe 30 G 0 001 G 0 001 G 3G 0 0001 G 0 0001 G 300 mG 0 01 mG AC Frequency Range 10 400 Hz AC RMS Accuracy 2 of reading 50 60 Hz AC RMS Freq Response 0 to 3 5 of reading 10 400 Hz All AC RMS specifications for sinusoidal input gt 1 of range AC Peak Accuracy 5 typical AC Peak Speed 5 ms for single peak Front Panel Display Type 4 line by 20 character vacuum fluorescent Display Resolution Up to 53 digits Display Update Rate 4 rdgs sec Vector Off 3 rdgs sec On Displays Units Gauss G Tesla T Units Multipliers u m k Annunciators FMS AC input signal DC DC input signal MAK Ma
2. LINE VOLTAGE SELECTION Use the following procedure to change the instrument line voltage selector Verify the fuse value whenever line voltage is changed WARNING To avoid potentially lethal shocks turn off gaussmeter and disconnect it from AC power before performing these procedures Identify the line input assembly on the instrument rear panel See Figure 6 1 Turn the line power switch OFF O Remove the instrument power cord With a small screwdriver release the drawer holding the line voltage selector and fuse Slide out the removable plastic fuse holder from the drawer Rotate the fuse holder until the proper voltage indicator shows through the window Verify the proper fuse value DO SNE Oe OW a GO Neue Re assemble the line input assembly in the reverse order 9 Verify the voltage indicator in the window of the line input assembly 10 Connect the instrument power cord 11 Turn the line power switch On I Service Lake Shore Model 460 Gaussmeter User s Manual Fuse Drawer Screwdriver Slot Line Cord Power Switch Input O Off I On Figure 6 1 Power Fuse Access 6 4 FUSE REPLACEMENT N LINE 10 5 Voltage 50 60 Hz 50 VA MAX FUSE DATA 100 120 V 1 0A 0 25 x 1 25 in T 220 240 V 0 5A 5 x 20 mm T F 460 6 1 eps Below is the procedure to remove and replace a line fuse There are two basic power configurations U S and International Units produced for use in the U S ha
3. Returned Format Alarm Inside Outside Query ALMIO term lt inout gt term n Refer to command for description ALML Input Format Remarks Alarm Low Point Command ALML lt field value gt term tnnn nn lt field value gt Returns sign 4 or 5 digits and places decimal point appropriate to range New value is entered on the same field range as the old value Setting value to zero first will change the setting range to present display range 4 31 Remote Operation Lake Shore Model 460 Gaussmeter User s Manual Device Specific Commands Continued ALML Input Returned Format Remarks ALMLM Input Returned Format Remarks ALMS Input Returned Format Remarks ANOD Input Format Remarks ANOD Input Returned Format ANOH Input Format Remarks 4 32 Alarm Low Point Query ALML term lt field value gt term tnnn nn Refer to command for description Use ALMLM to determine units multiplier Alarm Low Point Multiplier Query ALMLM term lt multiplier gt term a lt multiplier gt u micro 10 m milli 10 blank unity k kilo 10 Used with ALML query Alarm Status Query ALMS term lt state gt term n lt state gt 0 Off 1 On Queries current alarm status Off means no alarm condition exists On means an alarm exists Default Corrected Analog Out Command ANOD lt mode gt term n
4. If Lake Shore receives notice of any such defects during the Warranty Period and the defective Product is shipped freight prepaid back to Lake Shore Lake Shore will at its option either repair or replace the Product if it is so defective without charge for parts service labor or associated customary return shipping cost to the Purchaser Replacement for the Product may be by either new or equivalent in performance to new Replacement or repaired parts or a replaced Product will be warranted for only the unexpired portion of the original warranty or 90 days whichever is greater Lake Shore warrants the Product only if the Product has been sold by an authorized Lake Shore employee sales representative dealer or an authorized Lake Shore original equipment manufacturer OEM The Product may contain remanufactured parts equivalent to new in performance or may have been subject to incidental use when it is originally sold to the Purchaser The Warranty Period begins on the date the Product ships from Lake Shore s plant This limited warranty does not apply to defects in the Product resulting from a improper or inadequate installation unless OT amp V services are performed by Lake Shore maintenance repair or calibration b fuses software power surges lightning and non rechargeable batteries c software interfacing parts or other supplies not furnished by Lake Shore d unauthorized modification or misuse e operation outside
5. Local operation However the IEEE 488 and Serial Interfaces are included to provide remote operation If the Model 460 is connected to a suitably equipped computer the user has the option to permit or inhibit front panel operation The Local key acts as a toggle between local front panel functional or remote front panel disabled The letter R is displayed in the upper right side of the display to signify the Remote mode is activated The Interface key has three functions The first and second is to set the IEEE 488 Address and Terminators refer to Paragraph 4 1 The third is to set the Baud rate for the Serial Interface refer to Paragraph 4 2 Press Interface to display the three windows in the order shown below Select With A IEEE Address 17 Press the A or W keys to increment or decrement the IEEE Address to the required number Press Enter to accept the new number or Escape to leave the existing number The Model 460 automatically proceeds to the IEEE 488 Terminator display as follows Select With at Terminators Cr Lf Press the A or W keys to cycle through the following IEEE 488 Terminator choices Terminators are fixed to Cr Lf for the Serial Interface Cr Lf Carriage Return and Line Feed Lf Cr Line Feed and Carriage Return LF Line Feed EOI End Or Identify The Model 460 automatically proceeds to the Baud display as follows Select With A Baud 45 1 J6 Press the A or
6. Returned Format RELR Input Returned Format Remarks RELRM Input Returned Format Remarks RELS Input Format Remarks RELS Input Returned Format Remarks RELSM Input Returned Format Remarks 4 38 Relative Mode Query REL term lt state gt term n Refer to command for description Relative Mode Reading Query RELR term lt field value gt term tnnn nn lt field value gt Returns sign 4 or 5 digits and places decimal point appropriate to range Use RELRM to determine units multiplier and UNITS to determine gauss or tesla units Relative Mode Reading Multiplier Query RELRM lt multiplier gt term a lt multiplier gt u micro 10 m milli 10 blank unity k kilo 10 Used with RELR query Relative Mode Setpoint Command RELS lt field value gt term nnn nn lt field value gt Relative mode setpoint value with up to 5 digits resolution New value is entered on the same field range as the old value Setting value to zero first will change the setting range to present display range Relative Mode Setpoint Query RELS term lt field value gt term tnnn nn Refer to command for description Use RELSM to determine units multiplier Relative Mode Setpoint Multiplier Query RELSM term lt multiplier gt term a lt multiplier gt u micro 10 m milli 10 blank unity k k
7. MAXR Input Returned Format Remarks 4 36 Display Filter Window Command FWIN lt window gt term nn lt points gt Integer from 1 thru 10 Sets the filter window from 1 thru 10 The smaller the percentage the smaller the change in magnetic field that causes the filter to restart Refer to Paragraph 3 6 Display Filter Window Query FWIN term lt window gt term nn Refer to command for description Max Hold Command MAX lt state gt term n lt state gt 0 Off 1 On Works with the MAXR and MAXC commands Refer to Paragraph 3 2 Max Hold Query MAX term lt state gt term n Refer to command for description Max Clear Reset Command MAXC term This command initiates a Max Reset Upon entry the Max Hold function is zeroed out and a new peak is captured Refer to Paragraph 3 2 Max Reading Query MAXR term lt field value gt term nnn nn lt field value gt Returns plus sign 4 or 5 digits and decimal point appropriate to range Use MAXRM to determine units multiplier and UNITS to determine gauss or tesla units Remote Operation Lake Shore Model 460 Gaussmeter User s Manual Device Specific Commands Continued MAXRM Input Returned Format Remarks PRMS Input Format Remarks PRMS Input Returned Format RANGE Input Format Remarks RANGE Input Returned Format REL Input Format Remarks Max R
8. OPC Input Returned Remarks RST Input Remarks SRE Input Format Remarks Example SRE Input Returned Format STB Input Returned Format Remarks Operation Complete Command OPC term Generates an Operation Complete event in the Event Status Register upon completion of all pending selected device operations Send it as the last command in a command string Operation Complete Query OPC term 1 term Places a 1 in the output queue upon completion of all pending selected device operations Send as the last command in a command string Not the same as OPC Reset Instrument Command RST term Sets parameters to power up settings Configure Service Request Enable Register SRE lt bit weighting gt term nnn term Each bit has a bit weighting and represents the enable disable mask of the corresponding status flag bit in the Status Byte Register To enable a status flag bit send the command SRE with the sum of the bit weighting for each desired bit Refer to Paragraph 4 1 3 1 fora list of status flags To enable status flags 0 2 4 and 6 send the command SRE 85 term 85 is the sum of the bit weighting for each bit Bit Bit Weighting Event Name 0 1 FDR 2 4 ALM 4 16 OVI 6 64 SRQ 85 Service Request Enable Register Query SRE term lt bit weighting gt nnn term Refer to Paragraph 4 1 3 1 for a list of status flags Status Byte Query STB term l
9. lt mode gt 0 Off user selected scale 1 On default scale 2 Analog output controlled by remote interface refer to AOCON Sets default analog output status Default Corrected Analog Out Query ANOD term lt mode gt term n Refer to command for description Analog Out High Setpoint Command ANOH lt field value gt term nnn nn lt field value gt Enter sign 4 or 5 digits and place decimal point appropriate to range New value is entered on the same field range as the old value Setting value to zero first will change the setting range to present display range Remote Operation Lake Shore Model 460 Gaussmeter User s Manual Device Specific Commands Continued ANOH Input Returned Format Remarks ANOHM Input Returned Format Remarks ANOL Input Format Remarks ANOL Input Returned Format Remarks ANOLM Input Returned Format Remarks ANOS Input Format Remarks Remote Operation Analog Out High Setpoint Query ANOH term lt field value gt term tnnn nn Refer to command for description Use ANOHM to determine units multiplier Analog Out High Setpoint Multiplier Query ANOHM term lt multiplier gt term a lt multiplier gt u micro 10 m milli 10 blank unity k kilo 10 Used with ANOH query Analog Out Low Setpoint Command ANOL lt field value gt term nnn nn lt field
10. 0 240 in SOS max a i p i 4 Center of eli rotective 0 043 in max Ceramic Case ei C 460 C 6 eps Figure C 6 Transverse Hall Generator HGT 3010 HGT 3030 and HGCT 3020 Dimensions Table C 1 Cryogenic Hall Generator Specifications Maximum continuous current 300 mA 300 mA non heat sinked Magnetic sensitivity l nominal control 0 55 to 1 05 mV kG 0 55 to 1 05 mV kG current Maximum linearity error 1 0 RDG 30 to 30 kG 1 0 RDG 30 to 30 kG sensitivity vs field 2 0 RDG 150 to 150 kG 2 0 RDG 150 to 150 kG Zero field offset voltage lc nominal 200 uV max 200 uV max control current Operating temperature range 4 2 Kto 375K 4 2 K to 375 K Mean temperature coefficient of magnetic 0 01 K max 0 01 K max sensitivity Mean temperature coefficient of offset Ic 0 4 uV K max 0 4 uV K max nominal control current Mean temperature coefficient of resistance 0 6 K max 0 6 K max 34 AWG copper w Teflon insulation 34 AWG copper w Teflon insulation Hall Generators C 5 Lake Shore Model 460 Gaussmeter User s Manual lt 0 50 in e 10 in min 0 125 in Center of Active Area Ea Sos EE Ve mm d wm om mm mm 5 em 0 130 in max pe Ee O OOOO A max over Hall plate 0 028 in max over leads C 460 C 7 eps Figure C 7 Transverse Hall Generator HGT 1010 Dimensions Table C 2 Axial Hall Gener
11. Check for IEEE errors do error handling if needed Handle errors here End If If InStr strCommand lt gt 0 Then Check to see if query strReturn Space 100 Build empty return buffer Call ibrd intDevice strReturn Read back response If ibsta And EERR Then Check for IEEE errors do error handling if needed Handle errors here End If If strReturn lt gt Then Check if empty string strReturn RTrim strReturn Remove extra spaces and Terminators Do While Right strReturn 1 Chr 10 Or Right strReturn 1 Chr 13 strReturn Left strReturn Len strReturn 1 Loop Else strReturn No Response Send No Response End If frmIEEE txtResponse Text strReturn Put response in text on main form End If Loop End Sub Remote Operation 4 9 4 1 4 3 4 1 4 4 4 10 Lake Shore Model 460 Gaussmeter User s Manual IEEE 488 Interface Board Installation for Quick Basic Program This procedure works on an IBM PC or compatible running DOS or in a DOS window This example uses the National Instruments GPIB PCII IIA card 1 Install GPIB PCII IIA card using National Instruments instructions Install NI 488 2 software for DOS Version 2 1 1 was used for the example Verify that config sys contains the command device gpib pc gpib com Reboot the computer a Eet Run IBTEST to test software configuration Do not install the instrument before running IBTEST 6 Run IBCONF to configure the GPIB
12. DC Filter On with Filter Off PC Filter On 0 001 G 0 0001 G 0 0001 mT 0 00001 mT 0 0001G 0 00001G 300pT 0 01uT 0 001 uT 300 mG 0 01mG 0 001mG 30uT 0 001 uT 0 0001 uT Operation 3 7 Lake Shore Model 460 Gaussmeter User s Manual Select Range and Auto Range Continued 3 5 3 8 For manual ranging first press the desired channel in this case press the channel X key Then press the Select Range key This allows the user to see the full scale value for the present range as follows Select With AT LABEL D I kG Range Setting Channel zs Press the Select Range or A or W keys to cycle through the allowable full scale ranges for the probe installed Use the Enter key to accept the new range or Escape key to retain the old range Changing ranges in this way disables the Auto Range function until Auto Range is turned on NOTE When operating in AC Peak Mode only you cannot select the lowest range for the probe installed This is true for both Manual and Auto Range NOTE If a range is manually selected that is too small for the reading the reading will disappear and the letters OL for over load will be displayed If displaying the Vector reading any channel displaying OL will also cause the Vector display to display OL In Auto Range mode the Model 460 selects the range with the best resolution for the field being measured It can take up to 2 seconds for Auto Range to work so ma
13. Probe Orientation For Positive Measurement ccceeeeceeeeeeeeeeeeeaeeeeeeeceaeeeeaeeceaeeeaeeseaeesaeeseaeeeeaeeseaeeenates 3 26 Effect Of Angle On Measurements AA 3 27 CPB Seting ConfiQuratlon EE 4 6 DEV 12 Device Template Confiouraton 4 6 Typical National Instruments GPIB Configuration from IDBCONE ESE 4 11 Setial Interface Adapters i is eiiean elena Aceh dete ao a aao HLS aah eewaghns edges ig ee 4 14 2 Axis Probe Tip Defa S 2 iets setae gtvett ceed haeibeeaeioed eed eae ti eden ei eal ha eee ed 5 4 StAxiS Probe Tip ET TEE 5 5 Definition of Lake Shore Gamma Probe EEEn E Enare E nanena 5 5 Definition of Lake Shore 2 and 3 AXiS Probes AA 5 6 Definition of Lake Shore Robust Brass Stem Probes A 5 6 Definition of Lake Shore Transverse Probes AA 5 7 Definition of Lake Shore Tangential Probe AA 5 7 Definition of Lake Shore Axial Probes sssssssssneeseresestrnssttrntttttttttrttttnnnttnnnttrttttEnettEnnntEnnnn Ennn E Ennn E Ennen 5 8 Definition of Lake Shore Flexible Transverse PDrobes AA 5 9 Definition of Lake Shore Flexible Axial Probe ccccccecsesceeeeenceeeeeeeeeeeeeeeeeseneeeeeseaeeeeseaeeeessneeeesscnseeeseaees 5 9 Model MH 2 5 Helmholtz Col gedd VEER ves seeds ese vex ben cee da udee ca cesdec cov ae E a aien E a aea 5 10 Model MH 6 Helmholtz Coll eiis hiv Soha d e heel be pele edn Eed ec 5 11 Model MH 12 Helmholtz Col 5 11 Lake Shore Reference Maonets AAA 5 12 Model 4060 Zero Gauss Chamber 5 13 M
14. See Figure 5 16 Model 460 Gaussmeter User s Manual Hall Generator Cable Assembly The MCBL Cable Assembly connects a discrete Hall generator to the Model 460 Gaussmeter The cable ships with the HALLCAL EXE program which permits cable PROM programming through a PC or compatible computer serial port Because of the many calibration intricacies the user is responsible for measurement accuracy Refer to Appendix C MCBL 6 Hall Generator Cable Assembly 2 meters 6 feet long MCBL 20 Hall Generator Cable Assembly 6 meters 20 feet long Helmholtz Coils Provides stable low magnetic field when used with customer supplied power supply Often used to provide reference field to help check gaussmeter accuracy Three coils are available as follows Refer to Paragraph 5 3 MH 2 5 Helmholtz Coil 2 5 inch inner diameter field strength 830 G 1 A maximum continuous current 2 A coil resistance 3 Q See Figure 5 11 MH 6 Helmholtz Coil 6 inch inner diameter field strength 25 G 1 A maximum continuous current 2 A Coil Resistance 10 Q See Figure 5 12 MH 12 Helmholtz Coil 12 inch inner diameter field strength 12 G 1 A maximum continuous current 2 A Coil Resistance 20 Q See Figure 5 13 Reference Magnets High quality reference magnets are available in transverse flat and axial round configurations Refer to Paragraph 5 4 and see Figure 5 14 MRA 312 100 Axial Reference Magnet 0 312 inside diameter 100 G
15. Table of Contents Lake Shore Model 460 Gaussmeter User s Manual LIST OF TABLES Table No Title 4 1 IEEE 488 Interface Program Control Propertes 4 2 Visual Basic IEEE 488 Interface Program 4 3 Quick Basic IEEE 488 Interface Program 4 4 Serial Interface Specifications eceeecceceseesseeeseneeeeaeeseaeeeeaeeseaeeseaeessaeeeeaeeseeeseeeteaes 4 5 Serial Interface Program Control Properties A 4 6 Visual Basic Serial Interface Program 4 7 Quick Basic Serial Interface Program 4 8 Gommand Summary EE B 1 Conversion from CGS to SI Units 2 0 eee eeceeeeeeeeeeeeeeeeceeeeseeeeseaeeseaeeseaeeseaeeeseeeneeeeaes B 2 Recommended SI Values for Physical Constants A C 1 Cryogenic Hall Generator Specifications ccccccessssceceeeeeeeeeneeeeeseeeeseseeeeesenseeesees C 2 Axial Hall Generator Specifications cceeecceeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeaeeeeeeeeaeeseieeeseeeeeaes C 3 Transverse Hall Generator Specifications ceeeceeececeeeeeeeeeeeeeeeeeeeeeneeeeeeeeeteeeeeeeeeaes iv Table of Contents 1 0 1 1 Lake Shore Model 460 Gaussmeter User s Manual CHAPTER 1 INTRODUCTION GENERAL Lake Shore Cryotronics designed and manufactured the Model 460 3 Channel Gaussmeter in the United States of America The Model 460 is a high accuracy full featured gaussmeter ideally suited for the laboratory Model 460 features include 3 Axis or 3 Independent Channels Displays Each Axis Simultaneously Vector Magnitude
16. by a digital processor In Lake Shore controllers the heater output is maintained as a variable DC current source digital data Pertaining to data in the form of digits or interval quantities Contrast with analog data dimensionless sensitivity Sensitivity of a physical quantity to a stimulus expressed in dimensionless terms The dimensionless temperature sensitivity of a resistance temperature sensor is expressed as Sa T R dR dT which is also equal to the slope of R versus T on a log log plot that is Sa d InR d InT Note that the absolute temperature in kelvin must be used in these expressions drift instrument An undesired but relatively slow change in output over a period of time with a fixed reference input Note Drift is usually expressed in percent of the maximum rated value of the variable being measured dynamic data exchange DDE A method of interprocess communication which passes data between processes and synchronized events DDE uses shared memory to exchange data between applications and a protocol to synchronize the passing of data dynamic link library DLL A module that contains code data and Windows resources that multiple Windows programs can access electromagnet A device in which a magnetic field is generated as the result of electrical current passing through a helical conducting coil It can be configured as an iron free solenoid in which the field is produced along the axis of the coil or an iron cored
17. unsigned i e the positive or negative aspect of the field reading is ignored Refer to Paragraph 3 10 Turns the alarm feature on or off Press and hold the Alarm On Off key to turn the audible alarm on or off and select the alarm to activate inside or outside the range Refer to Paragraph 3 10 This key is used to select local or remote operation When set to Local the unit responds to front panel controls When set to Remote the unit is controlled via the IEEE 488 Interface Refer to Paragraph 3 11 Sets the bus address and terminators for the IEEE 488 Interface and Baud rate for the Serial Interface Refer to Paragraph 3 11 Use this key to set the display brightness Refer to Paragraph 3 12 Used to set the source and scaling of the Corrected Analog Output The scaling of the three Monitor Analog Outputs cannot be modified Refer to Paragraph 3 13 Operation Lake Shore Model 460 Gaussmeter User s Manual Front Panel Keypad Definitions Continued Escape Terminates a function without making changes to the existing settings Press and hold the Escape key for 20 seconds to reset the instrument and return parameters to factory default values Refer to Paragraph 3 15 A The up triangle A serves two functions The first is to toggle between various settings shown in the display The second is to increment a numerical display v The down triangle V serves two functions The first is to toggle between various settings shown
18. 0 kG has now been placed into memory Changes to the Corrected Analog Output are immediately observable For best results there should be at least 100 counts between minimum and maximum for the range For example if the 3 0000 kG range was selected and if the minimum scale setting was 1 0000 kG the maximum setting should be 1 0100 kG or greater Monitor Analog Out There are three Monitor Analog Outputs on the rear panel of the Model 460 The three outputs correspond to channels X Y and Z There is no monitor output for Vector Magnitude The Monitor Analog Outputs are real time analog signals proportional to the magnetic field The scale of each Monitor Analog Output is 3 volts for full scale of selected range The Monitor Analog Outputs are not as accurate as the Corrected Monitor Output but have the full DC to 400 Hz bandwidth of the AC measurement Most of the error is on lower ranges and results from zero offsets in the probe and instrument The error can be minimized if the output voltage observed at zero field can be subtracted from the live output See Figure 3 4 for the Monitor Analog Output frequency response O Phase Shift Degrees 150 100 50 100 150 200 DC 100 Frequency Hertz Figure 3 4 Monitor Analog Output Frequency Response Percent Relative Output C 460 3 4 eps Operation Lake Shore Model 460 Gaussmeter User s Manual 3 14 LOCKING AND UNLOCKING THE KEYBOARD The Model
19. 10 0 1019 2 588 20 0 0338 0 8118 30 0 0100 0 2546 40 0 00314 0 07987 ampere The constant current that if maintained in two straight parallel conductors of infinite length of negligible circular cross section and placed one meter apart in a vacuum would produce between these conductors a force equal to 2 x 1077 newton per meter of length This is one of the base units of the SI ampere turn A MKS unit of magnetomotive force equal to the magnetomotive force around a path linking one turn of a conducting loop carrying a current of one ampere or 1 26 gilberts ampere meter A m The SI unit for magnetic field strength H 1 ampere meter 47 1000 oersted 0 01257 oersted analog data Data represented in a continuous form as contrasted with digital data having discrete values analog output A voltage output from an instrument that is proportional to its input From an instrument such as a digital voltmeter the output voltage is generated by a digital to analog converter with a discrete number of voltage levels anode The terminal that is positive with respect to the other terminal when the diode is biased in the forward direction Anode cathode area A measure of the size of a two dimensional surface or of a region on such a surface area turns A coil parameter produced by the multiplication of the area of a magnet and number of turns Gives an indication of the sensitivity of a coil B Symbol for magnetic flux densit
20. 18 wm RJ 11 to DE 9 Adapter Adapts RJ 11 receptacle to female DE 9 connector Connects Model 460 to RS 232C Serial Port on rear of Customer s computer See Figure 5 19 4004 IEEE 488 Interface Cable Connects Model 460 to customer supplied computer with IEEE 488 Interface Cable is 1 meter 3 feet long Rack Mounting Kit Mounting ears and hardware to attach one Model 460 to a 483 mm 19 inch rack mount space Accessories amp Probes 5 1 Lake Shore Model 460 Gaussmeter User s Manual 5 2 4030 XX 4060 4065 MAN 460 MCBL XX MH XX MRA XXX MRT XXX Hall Probe Stand This moveable probe stand consists of a 30 mm square post mounted ona 180 x 130 x 22 5 mm thick base plate A probe holder is integrated into the stand The holder can be moved up or down and fixed at any angle and location along the post Two models are available as follows Consult factory for other post heights 4030 12 Hall probe stand with 12 inch tall post and probe holder to accept 3 8 inch diameter Hall probe handle 4030 24 Hall probe stand with 24 inch tall post and probe holder to accept 3 8 inch diameter Hall probe handle Standard Zero Gauss Chamber Calibrates standard probes Size 32 x 32 x 61 mm 1 3 x 1 3 x 2 4 in Bore 12 mm dia x 51 mm deep 0 5 x 2 in See Figure 5 15 Large Zero Gauss Chamber Calibrates Gamma Probe Size 57 x 53 x 305 mm 2 25 x 2 1 x 12 in Bore 19 mm dia x 279 mm deep 0 75 x 11 in
21. 39 Lake Shore Model 460 Gaussmeter User s Manual Probe Specific Commands Continued ONOFF Input Returned Format SNUM Input Returned Format TCOMP Input Format Remarks TCOMP Input Returned Format TYPE Input Returned Format Remarks ZCAL Input Remarks 4 40 Probe On Off Query ONOFF term lt state gt term n Refer to command for description Probe Serial Number Query SNUM term lt serial gt term annnnnnnnn lt serial gt The current probe serial number format is Hnnnnn though there is room for up to a ten character response Temperature Compensation Command TCOMP lt state gt term n lt state gt 0 Off 1 On Turns set temperature compensation On or Off If off probe temperature compensation if present is ignored Refer to Paragraph 3 7 Temperature Compensation Query TCOMP term lt state gt term n Refer to command for description Probe Type Query TYPE term lt type gt term n lt type gt 0 High Sensitivity HSE 1 High Stability HST 2 Ultra High Sensitivity UHS Refer to Paragraph 5 2 Zero Probe Command ZCAL term This command initiates the Zero Probe function Place probe in the Zero Gauss Chamber first and then enter the ZCAL command Refer to Paragraph 3 3 Remote Operation Lake Shore Model 460 Gaussmeter User s Manual CHAPTER 5 ACCESSORIES AND PROBES 5 0 GENERAL This chapter
22. AC selection provides the user with the choice of Peak or RMS readings This function is not available for Vector Magnitude Refer to Paragraph 3 5 The AC selection provides the user with the choice of Peak or Root Mean Square RMS readings AC peak can also be used with the Max Hold feature to measure single pulse peak values This function is not available for Vector Magnitude Refer to Paragraph 3 5 Turns the filter on or off and allows configuration of filter Filter on enables high resolution DC readings Press and hold Filter key to select Field Compensation and Temperature Compensation on or off This function is not available for Vector Magnitude Refer to Paragraph 3 6 Changes display units from gauss to tesla Gauss G is used in the cgs system where 1 G 10 T Tesla T is used in the SI system where 1 T 104 G This is a global setting applies to all channels Refer to Paragraph 3 8 With the relative feature turned on this key is used to capture the present field reading as the relative setpoint You also have the option of entering a number via the numerical keypad Works with the Relative On Off key Refer to Paragraph 3 9 Turns on the relative feature which displays the positive or negative deviation from the relative setpoint The relative feature can also be used with the Max Hold and Alarm features Refer to Paragraph 3 9 This key is used to set the high and low alarm points The alarm setpoints are absolute
23. CR ODH LF OAH Command Rate 20 commands per second maximum Message Strings A message string is a group of characters assembled to perform an interface function There are three types of message strings commands queries and responses The computer issues command and query strings through user programs the instrument issues responses Two or more command strings can be chained together in one communication but they must be separated by a semi colon Only one query is permitted per communication but it can be chained to the end of a command The total communication string must not exceed 64 characters in length A command string is issued by the computer and instructs the instrument to perform a function or change a parameter setting The format is lt command mnemonic gt lt space gt lt parameter data gt lt terminators gt Command mnemonics and parameter data necessary for each one is described in Paragraph 4 3 Terminators must be sent with every message string Lake Shore Model 460 Gaussmeter User s Manual Message Sirings Continued 4 2 5 4 2 6 4 16 A query string is issued by the computer and instructs the instrument to send a response The query format is lt query mnemonic gt lt gt lt space gt lt parameter data gt lt terminators gt Query mnemonics are often the same as commands with the addition of a question mark Parameter data is often unnecessary when sending queries Query mnemonics
24. EES dgeeatsateedeagadgneatbanges 4 14 4 2 2 we UE TEE 4 15 4 2 3 Character Fomati a aaa a a nde eee ied eee ee 4 15 4 2 4 Message SthiNgS reatie Pisces Sege Eer Ee tg Eeer 4 15 4 2 5 Message Flow CONTON ridses oserei a teases eaten aii andi lei Geet 4 16 4 2 6 Changing EL HSC 4 16 4 2 7 Serial Interface Basic Progorams 4 17 4 2 7 1 Visual Basic Serial Interface Program Getup 4 17 4 2 7 2 Quick Basic Serial Interface Program Getup 4 20 4 2 8 MPOUDIE SHOOUING EE 4 22 4 3 Command SUMMA tiated i E eiii ea EEEE AU adap dee cheered a elena 4 22 4 3 1 Common Commands siesena ieres e estr dines nai idl atid died aiid 4 24 4 3 2 ue nl EE 4 27 4 3 3 Device Specific Commande AAA 4 30 4 3 4 Probe Specific COMMANA S a ar ea a a aa aea ere a oeat Eoaea E AE ear aa aI SPEARE AEE En TENTAS 4 39 5 ACCESSORIES AND PROBES sj 02escciesccctaceescecsntesenceenedeccuseystecsnsstl eege geg 5 1 5 0 Generales chai bce ae i en ee EE 5 1 5 1 de EE 5 1 5 2 PCCOSSONOS EE 5 1 5 3 Lake Shore Standard Probes cssccescecsseecesceceececeaeeesaeeceanesnaceceaaesaaeseaeesssaeseaeesesaeseanessaessanensaaes 5 3 5 3 1 Probe Selection Criteria es ccecesccciececsccescea dE SEHR REENEN dE devine ENNEN ie irti edits 5 3 5 3 2 Radiation Effects on Gaussmeter Probes AA 5 4 5 3 3 Ee EREM 5 4 5 3 4 Probe SpeCifiGatlons tive a r a a a oy hases cdeceucg exe teases aana a e testa eta aae a EER a iiaea 5 5 5 4 Helmholtz Coil Low Field Standards AA 5 10 5 5 Reference Magn
25. Gb cm 103 47 A m Volume magnetization Volume magnetization 108 47 3 Ai Ai 3 Magnetic polarization 3 4 2i intensity of magnetization emu cm 4r x 10 T Wb m Mass magnetization emu g Magnetic moment m emu erg G 10 4r x 107 Wbem kg tesla J T Magnetic dipole moment Wm d ng dimensionless Henry per meter Volume susceptibility X emu cm 47 x 10 7 H m Wb Asm KC 8 weber Wb Magnetic Flux maxwell Mx Gecm volt second Ves b 1 3 3 Mass susceptibility cm g emu g Anon 1 0 10 Mech Permeability dimensionless 4n x 107 _ H m Whi Asm Relative permeability lu not defined dimensionless u Hr E erg cm 10 Jim DN Demagnetization factor DN LL dimensiontess TL us LL dimensionless An x 10 m3 mol Molar susceptibility cm mol emu mol Matt e Mute NOTES a Gaussian units and cgs emu are the same for magnetic properties The defining relation is B H Ach b Multiply a number in Gaussian units by C to convert it to SI e g 1 G x 10 T G 10 T c Sl Syst me International d Unit s has been adopted by the National Bureau of Standards Where two conversion factors are given the upper one is recognized under or consistent with SI and is based on the definition B po H M where to po 4x x 107H m The lower one is not recognized under SI and is based on the definition B ua J where the symbol is often used in place of J d 1 ga
26. Output Query SRE Service Request Enable Query AOCON Analog Output Control Mode Cmd STB Status Byte Query AOCON Analog Output Control Mode Query TST Self Test Query AUTO Auto Range Cmd WAI Wait To Continue Cmd AUTO Auto Range Query Interface Commands CHNL Channel Command ADDR IEEE Address Cmd CHNL Channel Query ADDR IEEE Address Query FIELD Field Reading Query BAUD Serial Interface Baud Rate Cmd FIELDM Field Multiplier Query BAUD Serial Interface Baud Rate Query FILT Display Filter Cmd BRIGT Display Brightness Cmd FILT Display Filter Query BRIGT Display Brightness Query ENUM Display Filter Points Cmd CODE Keyboard Lock Code Cmd FNUM Display Filter Points Query CODE Keyboard Lock Code Query FWIN Display Filter Window Cmd END EOI Status Cmd FWIN Display Filter Window Query END EOI Status Query MAX Max Hold Cmd FAST Fast Data Mode Cmd MAX Max Hold Query FAST Fast Data Mode Query MAXC Max Clear Reset Cmd KEY Key Pressed Query MAXR Max Reading Query LOCK Keyboard Lock Cmd MAXRM Max Reading Multiplier Query LOCK Keyboard Lock Query PRMS Peak RMS Field Cmd MODE Local Remote Mode Cmd PRMS Peak RMS Field Query MODE Local Remote Mode Query RANGE Manual Range Cmd SLEEP Current Source Cmd RANGE Manual Range Query SLEEP Current Source Query REL Relative Mode Cmd TERM Terminator Cmd REL Relative Mode Query TERM Terminator Query RELR Relative Mode Reading Query Device Specific Commands RELRM Relative Mode Multiplier Q
27. PCII IIA board and dev 12 Set the EOS byte to OAH and Enable Repeat Addressing to Yes See Figure 4 3 IBCONF modifies gpib com 7 Connect the instrument to the interface board and power up the instrument Verify the address is 12 and terminators are CR LF Quick Basic Program The IEEE 488 interface program in Table 4 3 works with QuickBasic 4 0 4 5 or Qbasic on an IBM PC or compatible running DOS or in a DOS window It assumes your IEEE 488 GPIB card is installed and operating correctly refer to Paragraph 4 1 4 3 Use the following procedure to develop the Serial Interface Program in Quick Basic 1 Copy c gpib pc Qbasic qbib obj to the QuickBasic directory QB4 2 Change to the QuickBasic directory and type link Jo qbib obj bqlb4x lib where x 0 for QB4 0 and 5 for QB4 5 This one time only command produces the library file qbib qlb The procedure is found in the National Instruments QuickBasic readme file Readme qb 3 Start QuickBasic Type qb I qbib qlb Start QuickBasic in this way each time the IEEE interface is used to link in the library file 4 Create the IEEE example interface program in QuickBasic Enter the program exactly as presented in Table 4 3 Name the file ieeeexam bas and save 5 Run the program 6 Type a command query as described in Paragraph 4 1 4 5 Type EXIT to quit the program Remote Operation Lake Shore Model 460 Gaussmeter User s Manual National Instruments Primary G
28. PO aaa NE aa aAA O oaa arenei eSEE 2 2 2 4 Line Input Assembly isi innnionnron e n e e a E e i a iive 2 3 2 4 1 Line Voltage and Fuse Verification eeeeeeeeseeeeeeneeeereneeeeeeaeeeeeeeneeeseaeeeeeeneeeeeeeaeeesenaeeseneneeeeeee 2 3 2 4 2 Eet EE E 2 3 2 4 3 POWER SWICK EEA A R EES EA 2 3 2 5 Probe Input Connection sierran te Ze dere sa dea a ea aaraa E Eoaea AE AAAA EE anaiei aaien 2 3 2 5 1 Attachment To A Hall Generator 2 4 2 6 Corrected and Monitor Analog Outputs ecceeeeeeeeeeeeeeeceaeeeeeeeceaeeseeeeseaeeeaeeseaeeesaeeseaeesnatestaeeenaees 2 4 2 7 Initial Setup and System Checkout Procedure ccceeceeeeeeseeeeeeeeeeeeeseaeeseaeeseaeeseaeeseaeeseaeeteeeeeaeete 2 4 3 OPERATION BEE 3 1 3 0 Generals iere Satis tees TREIE AALE lived dt deg eet eee 3 1 3 1 Definition of Front Panel Controls A 3 1 3 1 1 Front Panel Keypad Definitions cceceseenceceseeeeeeeeeeceeeneneeeeeseeeeenseaeesesenceseeseeeesensasenenenseeeescees 3 1 3 1 2 RENERT E EE 3 3 3 1 3 Front Panel Navigation eaa a aeaea a aa a a aa aa aaa aa aa aaah da adea E asiaate paai 3 4 3 1 4 Channel CU aniei ESA ee e E eea a ee ae eas 3 4 3 1 5 ATLETE ro ESTO LO IKE E EE inde eS Oe E 3 5 3 2 Max Holdand Max TEE 3 5 3 3 PAKOM AKE ol E E E 3 6 3 4 Select Range and Auto Range ssai teal a iaae DEENEN 3 7 3 5 AC DCand Peak RMS nenion issie rines aeea E ach deed ENAT TEN delle Ean E area Tr 3 8 3 6 E EAE EA EE EE E A ENER dd eege 3 9 3 7 Field and Temperatur
29. Reading Resolution to 5 Digits Accuracy to 0 10 of Reading Peak Capture Analog Voltage Outputs IEEE 488 and Serial Interface PRODUCT DESCRIPTION The Model 460 three channel Hall effect gaussmeter is the best choice for applications requiring three axis measurements or three simultaneous single axis measurements This instrument combines the performance of three Model 450 Gaussmeters into one package making it an excellent value The large display shows readings for all three channels simultaneously The fourth display can be used to show Vector Magnitude when necessary Probes The Lake Shore strength in magnetic measurement instrumentation is rooted in the ability to make Hall effect sensors and probes This strength is most apparent when multiple axis measurements are required The Model 460 is optimized for use with Lake Shore two and three axis probes as well as standard Hall sensors single axis probes and probe accessories The instrument automatically reads data stored in the probe connector to identify probe type and capability If standard products are not sufficient custom probes and assemblies are can be made to order Measurement Features Easy access to probe information that is stored in the probe allows several features which improve the measurement capability of the instrument Probe type tells the instrument how to configure itself for multiple axis measurements and what field ranges are available for display aut
30. after resetting the interface check the repeat addressing setting It should be enabled Old Installation No Longer Working 1 Power instrument off then on again to see if it is a soft failure 2 Power computer off then on again to see if the IEEE card is locked up 3 Verify that the address has not been changed on the instrument during a memory reset 4 Check all cable connections Intermittent Lockups 1 Check cable connections and length 2 Increase delay between commands to 50 ms to make sure instrument is not being over loaded OP ON Ce GOAN e Remote Operation 4 13 4 2 4 2 1 4 14 Lake Shore Model 460 Gaussmeter User s Manual SERIAL INTERFACE OVERVIEW The serial interface used in the Model 460 is commonly referred to as an RS 232C interface RS 232C is a standard of the Electronics Industries Association EIA that describes one of the most common interfaces between computers and electronic equipment The RS 232C standard is quite flexible and allows many different configurations However any two devices claiming RS 232C compatibility cannot necessarily be plugged together without interface setup The remainder of this paragraph briefly describes the key features of a serial interface that are supported by the instrument A customer supplied computer with similarly configured interface port is required to enable communication Physical Connection The Model 460 has an RJ 11 connector on the rear panel for
31. and parameter data if necessary is described in Paragraph 4 3 Terminators must be sent with every message string The computer should expect a response very soon after a query is sent A response string is the instruments response or answer to a query string The instrument will respond only to the last query it receives The response can be a reading value status report or the present value of a parameter Response data formats are listed along with the associated queries in Paragraph 4 3 The response is sent as soon as possible after the instrument receives the query Typically it takes 10 ms for the instrument to begin the response Some responses take longer Message Flow Control It is important to remember that the user program is in charge of the serial communication at all times The instrument can not initiate communication determine which device should be transmitting at a given time or guarantee timing between messages All of this is the responsibility of the user program When issuing commands only the user program should e Properly format and transmit the command including terminators as one string e Guarantee that no other communication is started for 50 ms after the last character is transmitted e Not initiate communication more than 20 times per second When issuing queries or queries and commands together the user program should e Properly format and transmit the query including terminators as one string e Prepare to rece
32. are two ways to enter the relative setpoint The first method captures the field reading nulling the present field To use the relative function first press the desired channel For this example press the channel X key Then press the Relative Set key and observe the following display Enter Relative Sete H 4927 kG Using D 8563 Setting Channel a The first line is the just captured value 0 0922 kG in the above example The next line shows the value the relative setpoint was previously using 0 8563 kG Press Enter to accept the new setpoint or Escape to retain the old value and quit the Relative Set function If the captured value is not what you want then you may enter the exact field value using the numeric keypad Press the Relative Set key and change the setpoint by pressing number keys or using the A or V keys Use the Select Range key to enter a setpoint different from the range currently being displayed Press Enter to accept the new setpoint or Escape to return to the old value Once the relative setpoint is established push the Relative On Off key to initiate the relative function The Relative On message is briefly shown in the proper line of the display The display for that channel will then show the plus or minus deviation from the setpoint A small delta A is displayed to signify the relative display H DD kG DC a H 25776 kG DC H 94952 kG DC 94311 kG aide For example Channel X is s
33. as physically installed in the instrument Archival copies are strictly forbidden You may not decompile disassemble or reverse engineer the firmware If you suspect there are problems with the firmware return the instrument to Lake Shore for repair under the terms of the Limited Warranty specified above Any unauthorized duplication or use of the Model 460 firmware in whole or in part in print or in any other storage and retrieval system is forbidden TRADEMARK ACKNOWLEDGMENT Many manufacturers and sellers claim designations used to distinguish their products as trademarks Where those designations appear in this manual and Lake Shore was aware of a trademark claim they appear with initial capital letters and the or symbol CalCurve Carbon Glass Cernox Duo Twist Gamma Probe Quad Lead Quad Twist Rox SoftCal and Thermox are trademarks of Lake Shore Cryotronics Inc MS DOS and Windows 95 98 NT 2000 are trademarks of Microsoft Corp NI 488 2 is a trademark of National Instruments PC XT AT and PS 2 are trademarks of IBM Copyright 1993 1999 2001 2003 2004 2009 and 2014 2015 by Lake Shore Cryotronics Inc All rights reserved No portion of this manual may be reproduced stored in a retrieval system or transmitted in any form or by any means electronic mechanical photocopying recording or otherwise without the express written permission of Lake Shore Rev 2 7 P N 119 012 9 March 201
34. available from this office Units for Magnetic Properties C1 0 C2 0 C2 1 Lake Shore Model 460 Gaussmeter User s Manual APPENDIX C HALL GENERATORS GENERAL This chapter provides theory of operation specifications mechanical drawings and definition of terminology Hall Generator theory of operation is detailed in Paragraph C2 0 Generic Hall generator hookup is detailed in Paragraph C3 0 Hookup to a Model 460 Gaussmeter is discussed in Paragraph C4 0 Specifications of the various available Hall generators are detailed in Paragraph C5 0 Finally the HALLCAL EXE program is detailed in Paragraph C6 0 Additional installation and calibration information is available in Lake Shore Document Number F075 00 00 Hall Generator Application Guide THEORY OF OPERATION The Hall effect was discovered by E H Hall in 1879 For nearly 70 years it remained a laboratory curiosity Finally development of semiconductors brought Hall generators into the realm of the practical A Hall generator is a solid state sensor which provides an output voltage proportional to magnetic flux density As implied by its name this device relies on the Hall effect The Hall effect is the development of a voltage across a sheet of conductor when current is flowing and the conductor is placed in a magnetic field See Figure C 1 Electrons the majority carrier most often used in practice drift in the conductor when under the influence of an extern
35. discussed in Paragraph 3 17 3 Finally accuracy considerations are provided in Paragraph 3 17 4 3 17 1 Changing Probes 3 24 A 512 byte Electrically Erasable Programmable Read Only Memory EEPROM is included in each probe The EEPROM stores specific information that the gaussmeter requires for operation The information includes serial number probe sensitivity and temperature and field compensation data CAUTION The probe must be connected to the rear of the instrument before applying power to the gaussmeter Probe memory may be erased if connected with power on When the instrument is powered up the probe memory is downloaded to the gaussmeter This is how the gaussmeter knows which ranges are available and which error correction to apply To change probes first turn power off remove the existing probe and then plug in the new probe When power is restored the characteristics of the new probe are downloaded to the gaussmeter memory Normal operation may continue after the new probe offset is nulled using the Zero Probe operation If the instrument is powered up with no probe attached the following message is displayed HO PROBE Power of to attach If any one channel has no probe attached excitation current to the channel is turned off the corresponding line of the display is blank and the message NO PROBE briefly appears when pressing and holding the X Y or Z channel key If the display remains blank
36. in the display The second is to decrement a numerical display Enter The Enter key is used to accept changes made in the field display Press and hold the Enter key to gain access to the Keypad Lock display A 3 digit code may be entered to lockout the keypad from accepting changes Refer to Paragraph 3 14 3 1 2 Front Panel Display In normal operation the four row by twenty character vacuum fluorescent display provides readings for Channel X on the first line Channel Y on the second line Channel Z on the third line and Vector Magnitude if selected on the fourth line of the display Other information is displayed when using the various functions on the keypad Each character is comprised of a 5 by 7 dot matrix Note the extra digit on the display will only appear if the channel is in DC mode and the Filter is turned on See Figure 3 2 Units kG Alarm G mG DC i Probe Orientation T PK Relative Remote DC Only mT Weg On On Field Reading uT MAX Channel X Bint Vector feta P Magnitude WS ai XYZ s This digit visible only in Vector Source XY DC and with Filter On or Max XZ YZ X Y C 460 3 2 eps Figure 3 2 Front Panel Display Definition Operation 3 3 3 1 4 3 4 Lake Shore Model 460 Gaussmeter User s Manual Front Panel Navigation Information in the first line of the display pertains to Channel X the second line to Channel Y third line to Channel Z and the fourth line to the Vector Magnitude To select a fu
37. increment or decrement the IEEE Address to the desired number Press Enter to accept new number or Escape to retain the existing number Pressing Enter displays the Terminators screen Select With at Terminators Cr Lf Press the A or W keys to cycle through the following Terminator choices CR LF LF CR LF and EOI To accept changes or the currently displayed setting push Enter To cancel changes push Escape Power down the Model 460 then back up again to allow other devices on the IEEE 488 bus to recognize a new Address or Terminator setting IEEE 488 Command Structure The Model 460 supports several command types These commands are divided into three groups 1 Bus Control refer to Paragraph 4 1 2 1 a Universal 1 Uniline 2 Multiline b Addressed Bus Control 2 Common refer to Paragraph 4 1 2 2 Interface and Device Specific refer to Paragraph 4 1 2 3 4 Message Strings Refer to Paragraph 4 1 2 4 Ge Bus Control Commande A Universal Command addresses all devices on the bus Universal Commands include Uniline and Multiline Commands A Uniline Command Message asserts only a single signal line The Model 460 recognizes two of these messages from the BUS CONTROLLER Remote REN and Interface Clear IFC The Model 460 sends one Uniline Command Service Request SRQ REN Remote Puts the Model 460 into remote mode IFC Interface Clear Stops current operation on the bus SRQ Service R
38. is displayed Then use the numeric keypad to enter the high alarm point After entering the desired high alarm point press Enter to accept the new value or Escape to retain the old value The display proceeds to the Low Alarm Point as follows Low Alarm Point H d 2 kG Setting Channel a The initial range displayed is the same as the latest probe range To set an alarm in a different range push the Select Range key until the proper range is displayed Then use the numeric keypad to enter the low alarm point After entering the desired alarm point press Enter to accept the new value or Escape to retain the old value The alarm setpoints are absolute unsigned i e only the magnitude of the field reading is used Once the proper high and low alarm points are entered press the Alarm On Off key to activate the alarm The message Alarm On briefly appears on the lower line of the display the musical note will turn on steady in the upper right hand corner of the display signifying alarm on To turn the alarm off again press the Alarm On Off key The message Alarm Off briefly appears When a magnetic item is within tolerance i e the field reading is inside the alarm setpoints the musical note will flash and if turned on the audible alarm will sound Operation 3 15 Lake Shore Model 460 Gaussmeter User s Manual 3 11 LOCAL AND INTERFACE Normal operations from the front panel and keypad are referred to as
39. kG 3 T and the Gamma Probe operates on the 300 mG 30 uT and 3 G 300 uT ranges If none of the standard probe configurations seem to fit your needs always remember that Lake Shore can provide custom probes to meet your physical temperature and accuracy requirements Contact Lake Shore with details of your special requirements Accessories amp Probes 5 3 5 3 2 5 3 3 5 4 Lake Shore Model 460 Gaussmeter User s Manual Radiation Effects on Gaussmeter Probes The HST and HSE probes use a highly doped indium arsenide active material The HST material is the more highly doped of the two and therefore will be less affected by radiation Some general information relating to highly doped indium arsenide Hall generators is as follows e Gamma radiation seems to have little effect on the Hall generators e Proton radiation up to 10 Mrad causes sensitivity changes lt 0 5 e Neutron cumulative radiation gt 0 1 MeV 10 5 sq cm can cause a 3 to 5 decrease in sensitivity e In all cases the radiation effects seem to saturate and diminish with length of time exposed 2 Axis and 3 Axis Probes At the tip of Lake Shore 2 Axis probes are one transverse and one axial Hall sensor 3 Axis probes contain two transverse and one axial Hall sensor These sensors are recessed in the non metallic Phenolic mounting block Phenolic permits AC and DC measurements whereas aluminum limits probes to DC or low frequency measurements The active
40. kG 0 kG 1 kG 2 kG 3 kG Example of operation with alarm triggered by Low Alarm readings OUTSIDE Point user defined setpoints High Alarm Point To enter this alarm setup push the Alarm Set key The user is first asked to enter the High Alarm Point as follows Hi ah Alarm Point 1 5006 kG Setting Channel a The initial range displayed is the same as the latest probe range To set an alarm in a different range push the Select Range key until the proper range is displayed Then use the numeric keypad to enter the high alarm point After entering the desired high alarm point press Enter to accept the new value or Escape to retain the old value The display proceeds to the Low Alarm Point as follows Low Alarm Poi nt H 5006 kG Setting Channel a The initial range displayed is the same as the latest probe range To set an alarm in a different range push the Select Range key until the proper range is displayed Then use the numeric keypad to enter the low alarm point After entering the desired alarm point press Enter to accept the new value or Escape to retain the old value Remember the alarm setpoints are absolute unsigned i e only the magnitude of the field reading is used Once the proper high and low alarm points are entered press the Alarm On Off key to activate the alarm The message Alarm On briefly appears on the lower line of the display the musical note will turn on steady in the upp
41. of a Model MCBL 6 or 20 Cable Assembly Because of the many intricacies involved with proper calibration the Customer must accept responsibility for the measurement accuracy Requirements Lake Shore Model 460 Gaussmeter connected via RS 232 to the computer in the COM1 port Lake Shore Model MCBL 6 or 20 Cable Assembly IBM or compatible CPU Hall generator meeting the sensitivity ranges given below Calibration or sensitivity constant and serial number of the Hall generator Operation 1 Set the Lake Shore Model 460 Gaussmeter to 300 Baud Refer Paragraph 3 11 of this User s Manual on how to set the Gaussmeter to communicate at 300 Baud Insert the 3 5 inch disk and type in the default drive A or B Type in HALLCAL This will execute the HALLCAL EXE program The program will prompt for the Probe serial number Any combination of 6 letters or number can be entered Press Enter when this is accomplished 5 The program will prompt for the probe type 0 or 1 Enter 0 for Hall generators with sensitivities between 5 5 and 10 5 mV kG 100 mA current Enter 1 for Hall generators with sensitivities between 0 55 and 1 05 mV kG 100 mA current 6 The program will prompt for the Calibration Constant Enter the magnetic sensitivity in mV kG at a control current of 100 mA Remember to account for the 420 Q input impedance of the Gaussmeter when calculating the proper load resistor to install 7 The program will display a
42. of the published specifications f improper site preparation or site maintenance g natural disasters such as flood fire wind or earthquake or h damage during shipment other than original shipment to you if shipped through a Lake Shore carrier This limited warranty does not cover a regularly scheduled or ordinary and expected recalibrations of the Product b accessories to the Product such as probe tips and cables holders wire grease varnish feed throughs etc c consumables used in conjunction with the Product such as probe tips and cables probe holders sample tails rods and holders ceramic putty for mounting samples Hall sample cards Hall sample enclosures etc or d non Lake Shore branded Products that are integrated with the Product To the extent allowed by applicable law this limited warranty is the only warranty applicable to the Product and replaces all other warranties or conditions express or implied including but not limited to the implied warranties or conditions of merchantability and fitness for a particular purpose Specifically except as provided herein Lake Shore undertakes no responsibility that the products will be fit for any particular purpose for which you may be buying the Products Any implied warranty is limited in duration to the warranty period No oral or written information or advice given by the Company its Agents or Employees shall create a warranty or in any way increase the sco
43. or the present value of a parameter Response data formats are listed along with the associated queries in Paragraph 4 3 Remote Operation 4 3 Lake Shore Model 460 Gaussmeter User s Manual 4 1 3 Status Registers 4 1 3 1 4 1 3 2 4 4 There are two status registers the Status Byte Register described in Paragraph 4 1 3 1 and the Standard Event Status Register in Paragraph 4 1 3 2 Status Byte Register and Service Request Enable Register The Status Byte Register consists of a single byte of data containing six bits of information about the condition of the Model 460 STATUS BYTE REGISTER FORMAT Bibs E EE E E ETS E E Weighting 128 64 32 16 8 4 2 1 Bit Name If the Service Request is enabled any of these bits being set will cause the Model 460 to pull the SRQ management low to signal the BUS CONTROLLER These bits are reset to zero upon a serial poll of the Status Byte Register These reports can be inhibited by turning their corresponding bits in the Service Request Enable Register to off The Service Request Enable Register allows the user to inhibit or enable any of the status reports in the Status Byte Register The SRE command is used to set the bits If a bit in the Service Request Enable Register is set 1 then that function is enabled Refer to the SRE command discussion Service Request SRQ Bit 6 Determines whether the Model 460 is to report via the SRQ line and four bits determine
44. placing the tip in the chamber 9 Place the probe in the zero gauss chamber Once inserted press the Channel key in this case Channel X then press the Zero Probe key You will see the following display Press Enter With Probe At Zero Setting Channel a 10 Press the Enter key The CALIBRATING message briefly displays followed by the normal display Do not move the probe while the CALIBRATING message displays There should be a near zero reading on the display when finished 11 Repeat Steps 9 and 10 for the Y and Z probes if present NOTE If the unit has performed well to this point the unit is functioning properly If you have a reference magnet available you can continue with the test using the magnet to verify the accuracy of the Model 460 Installation 2 5 Lake Shore Model 460 Gaussmeter User s Manual Initial Setup And System Checkout Procedure Continued 12 If continuing the procedure with a reference magnet ensure the probe can accommodate the range of the magnet Use the Range key to select the proper range Set the display for DC Finally since orientation of the probe is very selective press the Max Hold key This will capture the highest reading normally the reference magnet calibration value CAUTION Care must be exercised when handling the probe The tip of the probe is very fragile Any excess force may break the probe NOTE Probe readings are dependent upon the angle of the tip
45. precautions in Paragraph 6 1 electrostatic discharge in Paragraph 6 2 line voltage selection in Paragraph 6 3 fuse replacement in Paragraph 6 4 rear panel connector definitions in Paragraph 6 5 optional serial interface cable and adapters in Paragraph 6 6 operating software EPROM replacement in Paragraph 6 7 and error messages in Paragraph 6 8 There are no field serviceable parts inside the Model 460 Contact Lake Shore about specific problems with the Model 460 GENERAL MAINTENANCE PRECAUTIONS The following are general safety precautions unrelated to any other procedure in this publication Keep away from live circuits Installation personnel shall observe all safety regulations at all times Turn off system power before making or breaking electrical connections Regard any exposed connector terminal board or circuit board as a possible shock hazard Discharge charged components only when such grounding results in no equipment damage If a test connection to energized equipment is required make the test equipment ground connection before probing the voltage or signal to be tested Do not install or service equipment alone Do not reach into or adjust the equipment without having another person nearby capable of rendering aid If there is no power verify the power cord is plugged into a live outlet and that both ends are securely plugged in Next check the fuse refer to Paragraph 6 4 Use this procedure to periodically clean the in
46. second s results in a reading of 1 volt second v s Volt seconds are the primary unit of measurement for an integrator See Weber watt W The SI unit of power The watt is the power required to do work at the rate of 1 joule per second weber Wb The unit of magnetic flux in the mks system equal to the magnetic flux which linking a circuit of one turn produces in it an electromotive force of 1 volt as it is reduced to zero at a uniform rate in 1 second References 1 Sybil P Parker Editor Dictionary of Scientific and Technical Terms Fifth Edition New York McGraw Hill 1994 IBSN 0 07 042333 4 2 Christopher J Booth Editor The New IEEE Standard Dictionary of Electrical and Electronic Terms IEEE Std 100 1992 Fifth Edition New York Institute of Electrical and Electronics Engineers 1993 IBSN 1 55937 240 0 Definitions printed with permission of the IEEE 3 Nelson Robert A Guide For Metric Practice Page BG7 8 Physics Today Eleventh Annual Buyer s Guide August 1994 ISSN 0031 9228 coden PHTOAD A 6 Glossary of Terminology Magnetic flux density G Magnetic induction Lake Shore Model 460 Gaussmeter User s Manual APPENDIX B UNITS FOR MAGNETIC PROPERTIES Table B 1 Conversion from CGS to SI Units Gaussian Conversion SI and Quantity and CGS emu Factor CH Rationalized mks 4 tesla T Wb m eo ee gilbert G 10 47 ampere A Magnetic field strength 3 f magnetizing force oersted Oe
47. serial communication The original RS 232C standard specifies 25 pins but 9 pin 25 pin and RJ 11 connectors are commonly used in the computer industry For you convenience Lake Shore offers a Model 4001 RJ 11 Cable When combined with either the Model 4002 DB 25 Adapter or Model 4003 DE 9 Adapter this cable assembly can be used to connect the instrument to a computer with the corresponding connector type These adapters are described in Chapter 5 Accessories and Probes and are schematically diagramed in Figures 6 6 thru 6 8 Equipment with Data Communications Equipment DCE wiring can be connected to the instrument with a straight through cable However if the interface is for Data Terminal Equipment DTE a Null Modem Adapter is required to exchange the transmit TxD and receive RxD lines The instrument uses drivers to generate the transmission voltage levels required by the RS 232C standard These voltages are considered safe under normal operating conditions because of their relatively low voltage and current limits The drivers are designed to work with cables up to 50 feet in length To maintain Electromagnetic Compatibility EMC add the clamp on ferrite filter P N 109 053 included with the connector kit to the Serial Interface cable near the instrument rear panel when that interface is used LSCI Model 4002 RJ 11 SERIAL UO to DB 25 Serial Interface To customer supplied Adapter Output on rear of computer with DB 25 Mode
48. source gt Reading Full 3 axis gen HZ Reading gt XY fXpeating Y In the X Y plane Reading XZ a e In the X Z plane YF ae E In the Y Z plane La ce ee k Differential Reading MAX HOLD AND MAX RESET The Max Hold function displays the largest field magnitude measured since the last Max Reset When the Max Hold key is pressed the currently selected channel will change to display the MAX reading For example to turn Max Hold on for Channel Y press the Channel Y key followed by the Max Hold key You will see the following display 69278 kG DC Max Hold OW 969527 kG DC H 95525 kG YZ After a short timeout the Y channel display will return to normal with the Max hold value being displayed on the second line of the display as seen in the following display H 89275 kG DC RB 46776 kG Ha RH 96952 kG DC H 953245 kG sie Operation 3 5 Lake Shore Model 460 Gaussmeter User s Manual Max Hold and Max Reset Continued 3 3 3 6 The Max Reset key clears the Max Hold value The Max Hold value is also reset upon power up or when changing from AC or DC Max Hold may also be used in conjunction with the Relative display refer to Paragraph 3 9 Max Hold functions differently when being used with AC or DC fields as follows In DC operation the Max Hold feature holds the field reading that is largest in magnitude This is intended to monitor slo
49. then the Vector Magnitude Audible Alarm Command ALMB lt state gt term n lt state gt 0 Disabled 1 Enabled Audible Alarm Query ALMB term lt state gt term n Refer to command for description Remote Operation Lake Shore Model 460 Gaussmeter User s Manual Device Specific Commands Continued ALMH Input Format Remarks Alarm High Point Command ALMH lt field value gt term tnnn nn lt field value gt Returns sign 4 or 5 digits and places decimal point appropriate to range New value is entered on the same field range as the old value Setting value to zero first will change the setting range to present display range ALMH Input Returned Format Remarks Alarm High Point Query ALMH term lt field value gt term tnnn nn Refer to command for description Use ALMHM to determine units multiplier ALMHM Input Returned Format Remarks Alarm High Point Multiplier Query ALMHM term lt multiplier gt term a lt multiplier gt u micro 10 m milli 10 blank unity k kilo 10 Used with ALMH query ALMIO Input Format Remarks Alarm Inside Outside Command ALMIO lt inout gt term n lt inout gt 0 Outside or 1 Inside Instructs alarm feature to cause an active alarm state when the field reading is either inside of or outside of the high and low setpoint values Refer to Paragraph 3 10 ALMIO Input
50. to guarantee that data message strings do not collide and that no data is transmitted before the receiver is ready In this instrument appropriate software timing substitutes for hardware handshaking User programs must take full responsibility for flow control and timing as described in Paragraph 4 2 5 Character Format A character is the smallest piece of information that can be transmitted by the interface Each character is 10 bits long and contains data bits bits for character timing and an error detection bit The instrument uses 7 bits for data in the ASCII format One start bit and one stop bit are necessary to synchronize consecutive characters Parity is a method of error detection One parity bit configured for odd parity is included in each character ASCII letter and number characters are used most often as character data Punctuation characters are used as delimiters to separate different commands or pieces of data Two special ASCII characters carriage return CR ODH and line feed LF OAH are used to indicate the end of a message string Table 4 4 Serial Interface Specifications RJ 11 Connector DTE Connector Type Connector Wiring Voltage Levels Transmission Distance Timing Format Transmission Mode Baud Rate Handshake Character Bits Parity Terminators EIA RS 232C Specified 50 feet maximum Asynchronous Half Duplex 300 1200 9600 Software timing 1 Start 7 Data 1 Parity 1 Stop Odd
51. to periodically degauss the chamber If no professional degausser is available a bulk tape degausser Verity VS250 Data Devices PF211 or equivalent may be used Front View Side View ICH ww cr 12 2 mm 0 5 in diameter by 50 8 mm 2 in deep bore L 32 2 mm 61 mm 2 4 in 1 3 in C 460 5 15 eps Figure 5 15 Model 4060 Zero Gauss Chamber Front View 19 mm 0 75 in diameter opening 57 2 mm 2 25 in 31 8 mm 1 25 in 52 4 mm 2 1 in 304 8 mm 12 in lt Depth of Opening 279 4 mm 11 in Side View C 460 5 16 eps Figure 5 16 Model 4065 Large Zero Gauss Chamber 5 14 Accessories amp Probes Lake Shore Model 460 Gaussmeter User s Manual ooOoooooooooooi ZO ooooooooooo O o0000i O s0000 O Accessories amp Probes Cable Length 4 3 meters 14 feet See Figure 6 6 for wiring details C 460 5 17 eps Figure 5 17 Model 4001 RJ 11 Cable Assembly k seyoul ZZ ww gg 1 7 inches 0 6 inches See Figure 6 7 for wiring details C 460 5 18 eps Figure 5 18 Model 4002 RJ 11 to DB 25 Adapter r ww GZ Eau E H 60 3 mm 2 4 inches I See Figure 6 8 for wiring details 0 6 inches C 460 5 19 eps Figure 5 19 Model 4003 RJ 11 to DE 9 Adapter 6 0 6 1 6 2 Lake Shore Model 460 Gaussmeter User s Manual CHAPTER 6 SERVICE GENERAL This chapter covers general maintenance
52. upper limit to the coercive force compliance voltage See current source Curie temperature Tc Temperature at which a magnetized sample is completely demagnetized due to thermal agitation Named for Pierre Curie 1859 1906 a French chemist current source A type of power supply that supplies a constant current through a variable load resistance by automatically varying its compliance voltage A single specification given as compliance voltage means the output current is within specification when the compliance voltage is between zero and the specified voltage demagnetization when a sample is exposed to an applied field Ha poles are induced on the surface of the sample Some of the returned flux from these poles is inside of the sample This returned flux tends to decrease the net magnetic field strength internal to the sample yielding a true internal field Hint given by Hint Ha DM where M is the volume magnetization and D is the demagnetization factor D is dependent on the sample geometry and orientation with respect to the field deviation The difference between the actual value of a controlled variable and the desired value corresponding to the setpoint differential permeability The slope of a B versus H curve ua dB dH differential susceptibility The slope of a M versus H curve ya dM dH digital controller A feedback control system where the feedback device sensor and control actuator heater are joined
53. value gt Enter sign 4 or 5 digits and place decimal point appropriate to range New value is entered on the same field range as the old value Setting value to zero first will change the setting range to present display range Analog Out Low Setpoint Query ANOL term lt field value gt term tnnn nn Refer to command for description Use ANOLM to determine units multiplier Analog Out Low Setpoint Multiplier Query ANOLM term lt multiplier gt term a lt multiplier gt u micro 10 m milli 10 blank unity k kilo 10 Used with ANOL query Corrected Analog Output Source Command ANOS lt source gt term n lt source gt Defines the corrected analog output source channel Refer to Paragraph 3 13 1 4 33 Lake Shore Model 460 Gaussmeter User s Manual Device Specific Commands Continued ANOS Input Returned Format AOCON Input Format Remarks Example AOCON Input Returned Format AUTO Input Format AUTO Input Returned Format CHNL Input Format Remarks CHNL Input Returned Format 4 34 Corrected Analog Output Source Query ANOS term lt source gt term n Refer to command for description Analog Output Control Mode Command AOCON lt percent gt term tnnn nn lt percent gt Sets bipolar output voltage in percent of full scale Allows resolution of 0 01 As a safety precaution this setting always equals ze
54. which status reports to make If bits 0 1 2 4 and or 5 are set then the corresponding bit in the Status Byte Register will be set The Model 460 will produce a service request only if bit 6 of the Service Request Enable Register is set If disabled the Status Byte Register can still be read by the BUS CONTROLLER by means of a serial poll SPE to examine the status reports but the BUS CONTROLLER will not be interrupted by the Service Request The STB common command will read the Status Byte Register but will not clear the bits The bit assignments are discussed below as they pertain to the Status Byte Register These reports can only be made if they have been enabled in the Service Request Enable Register Standard Event Status ESB Bit 5 When bit 5 is set it indicates if one of the bits from the Standard Event Status Register has been set Refer to Paragraph 4 1 3 2 Overload Indicator OVI Bit 4 If the display has an overload condition on any channel this bit is set and a Service Request is issued if enabled Alarm ALM Bit 2 This bit is set when an alarm condition exists on any channel This condition will latch until acknowledged by the bus controller Range Change RNG Bit 1 Range changed in Auto Range mode on any channel Field Data Ready FDR Bit 0 When this bit is set new valid field readings are available Standard Event Status Register and Standard Event Status Enable Register The Standard
55. will always return to a known value at any specific ambient temperature The high permeability shell which surrounds the reference magnet serves two function 1 it shields the magnet from external field and 2 serves as the flux return path Physical damage to the outer shell can cause a permanent change in the gap flux density Reference magnets should not be dropped or physically abused Magnets of this type can have magnetic reference values ranging from 100 G to 20 kG but the most widely used value is 1 kG Reference magnet accuracy is typically 0 5 except for magnets of 200 G or less for these magnets the limit of error is generally 1 The reference magnet gap is nominally 0 060 inch but may range from 0 040 to 0 250 inch for special units The usable plateau in the reference gap generally encompasses an area of about 0 5 square inches In reference magnets used for axial field probes Alnico V or VI is the usual magnet material charged to saturation and stabilized down to a particular value The same temperature coefficients hold true as in the transverse probe and the same care in handling must be observed This assembly uses concentric mu metal shield cans to protect the magnet from the effects of external magnetic field Axial reference magnets are available in values up to 2 kG with 500 G being the most widely used value When a probe is inserted completely through the access guide three distinct magnetic peaks will be observe
56. 00 LINE INPUT ENTER COMMAND or EXIT CMD CMD UCASES CMD IF CMD EXIT THEN END CMD CMD TERM CALL IBWRT DEV12 CMD CALL IBRD DEV12 IN ENDTEST INSTR IN CHR 13 IF ENDTEST gt 0 THEN INS MIDS INS 1 ENDTEST 1 PRINT RESPONSE IN ELSE PRINT NO RESPONSE END IF GOTO LOOP2 Link to IEEE calls Clear screen Open communication at address 12 Terminators are lt CR gt lt LF gt Clear for return string Get command from keyboard Change input to upper case Get out on Exit Send command to instrument Get data back each time Test for returned string String is present if lt CR gt is seen Strip off terminators Print return string No string present if timeout Get next command Remote Operation Lake Shore Model 460 Gaussmeter User s Manual 4 1 4 5 Program Operation Once either example program is running try the following commands and observe the response of the instrument Input from the user is shown in bold and terminators are added by the program The word term indicates the required terminators included with the response ENTER COMMAND IDN Identification query Instrument will return a string identifying itself RESPONSE LSCI MODEL450 0 020303 term ENTER COMMAND FIELD Field reading query Instrument will return a string with the present field reading RESPONSE 12 345 term ENTER CO
57. 1 MRA 312 200 Axial Reference Magnet 0 312 inside diameter 200 G 1 MRA 312 300 Axial Reference Magnet 0 312 inside diameter 300 G 1 MRA 312 500 Axial Reference Magnet 0 312 inside diameter 500 G 1 MRA 312 1K Axial Reference Magnet 0 312 inside diameter 1 kG 1 MRA 312 2K Axial Reference Magnet 0 312 inside diameter 2 kG 1 MRT 062 200 Transverse Reference Magnet 0 062 gap 200 G 1 MRT 062 500 Transverse Reference Magnet 0 062 gap 500 G 1 MRT 062 1K Transverse Reference Magnet 0 062 gap 1 kG 0 5 MRT 062 2K Transverse Reference Magnet 0 062 gap 2 kG 0 5 MRT 062 5K Transverse Reference Magnet 0 062 gap 5 kG 0 5 MRT 062 10K Transverse Reference Magnet 0 062 gap 10 kG 5 MRT 343 50 Transverse Reference Magnet 0 343 gap 50 G 1 MRT 343 100 Transverse Reference Magnet 0 343 gap 100 G 1 Accessories amp Probes Lake Shore Model 460 Gaussmeter User s Manual Probe Extension Cables Four cables are available Each extension cable contains a EEPROM for calibration data Each extension cable must be matched to a specific probe To maintain probe accuracy that probe and extension cable must be calibrated together at Lake Shore The probe will exhibit its full accuracy if used without the extension cable Part numbers and cables lengths are defined as follows MPEC 10 Probe Extension Cable 3 meters 10 feet MPEC 25 Probe Extension Cable 7 6 meters 25 feet MPEC 50 Probe Extension Cabl
58. 1 Source handshake capability e RL1 Complete remote local capability e DC1 Full device clear capability e DTO No device trigger capability e CO No system controller capability e T5 Basic TALKER serial poll capability talk only unaddressed to talk if addressed to listen e L4 Basic LISTENER unaddressed to listen if addressed to talk e SR1 Service request capability e AH1 Acceptor handshake capability e PPO No parallel poll capability e E1 Open collector electronics NOTE The Model 460 IEEE 488 Interface requires that repeat addressing be enabled on the bus controller Instruments are connected to the IEEE 488 bus by a 24 conductor connector cable as specified by the standard Refer to Paragraph 6 5 1 Cables can be purchased from Lake Shore or other electronic suppliers Cable lengths are limited to 2 meters for each device and 20 meters for the entire bus The Model 460 can drive a bus with up to 10 loads If more instruments or cable length is required a bus expander must be used Remote Operation 4 1 4 1 2 1 4 2 Lake Shore Model 460 Gaussmeter User s Manual IEEE 488 Interface Settings If using the IEEE 488 interface you must set the IEEE Address and Terminators Press the Interface key The first screen selects Serial Interface Baud Rate and therefore is skipped by pressing the Enter key The Address screen is then displayed Select With A IEEE Address 17 Press the A or W keys to
59. 460 front panel keyboard may be locked preventing unauthorized changes to the settings To lock the keyboard press and hold the Enter key 10 seconds until the following display is seen Enter Code to Lock Keyrad Now enter the 3 digit lock code the factory default code is 123 Upon entry of the third number the display reverts to the normal display The keyboard is now locked After locking the keypad any attempt to change settings causes the following message to briefly be displayed Lock ect To unlock the keyboard again press and hold the Enter key until the following display is seen Enter Code to Unlock Keyrad Enter the lock code again Upon entry of the third number the display reverts to the normal display and the keyboard is unlocked The lock code may be changed using either the IEEE 488 or Serial Computer Interface If the instrument is reset the lock code will revert to 123 The instrument cannot be reset when the keyboard is locked Operation 3 21 Lake Shore Model 460 Gaussmeter User s Manual 3 15 FACTORY DEFAULT SETTINGS If the keypad is unlocked and the Model 460 is in local mode the user may press and hold Escape key for x20 seconds to return the instrument to factory default settings shown below Other gaussmeter calibration information and probe data are not affected by this reset The probe should be zeroed after completing this operation AC DC Filter Window 1
60. 5 Lake Shore Model 460 Gaussmeter User s Manual CE DECLARATION OF CONFORMITY Lake Shore Cryotronics Inc 575 McCorkle Blvd Westerville OH 43082 USA hereby declare that the equipment specified conforms to the following Directives and Standards Application of Council Directives 2006 95 EC LVD 2004 108 EC EMC Standards to which Conformity is declared EN 61010 1 2010 Overvoltage II Pollution Degree 2 EN 61326 1 2013 Class A Annex B Model Number 5 Pri Sip wfe fzo Scott Ayer Director of Quality and Compliance Position Lake Shore Model 460 Gaussmeter User s Manual Electromagnetic Compatibility EMC for the Model 460 3 Channel Gaussmeter Electromagnetic Compatibility EMC of electronic equipment is a growing concern worldwide Emissions of and immunity to electromagnetic interference is now part of the design and manufacture of most electronics To qualify for the CE Mark the Model 460 meets or exceeds the generic requirements of the European EMC Directive 89 336 EEC as a CLASS A product A CLASS A product is allowed to radiate more RF than a CLASS B product and must include the following warning WARNING This is a CLASS A product In a domestic environment this product may cause radio interference in which case the user may be required to take adequate measures The instrument was tested under normal operating conditions with sensor and interface cables attached If the installation and operating i
61. 5 on the numerical keypad and press the Enter key A minimum output of 1 5 kG has now been placed into memory Changes to the Corrected Analog Output are immediately observable The second example is an asymmetrical scaling which demonstrates the versatility of user selectable scaling i 1 5 kG penn 0kG 40 5 kG 41 kG 2 kG 42 5 kG 43 kG EE 3 V 2V 1V a HV 2 V 43 V To enter this scale press the Analog Out Key Press the Analog Out A or W key to cycle the arrow to User as shown below Select With af Anal o3 Out Aer User Press the Analog Out A or V key to cycle the arrow to Def Default Press the Enter key The display will automatically step to the Analog Output Source selection display shown below Select With A Anal o3 Out Source Press the A or W key to cycle the analog output source from channel X Y Z or Vector In this case we chose Channel X Press the Enter key and observe the following display Enter Max outeut 3 DHHG kG Operation 3 19 Lake Shore Model 460 Gaussmeter User s Manual Corrected Analog Out Continued 3 13 2 3 20 Enter the number 3 on the numerical keypad and press the Enter key A maximum output of 3 0 kG has now been placed into memory Upon pressing Enter the following display will appear Enter Min output H BEE kG Enter the numbers 0 0 on the numerical keypad and press the Enter key A minimum output of 0
62. 6 BC 683 415 G BC 22 213 D ch Differential readings X Z Xreading Yreading are possible with the Model 460 X Y and Z Axis with Max Hold on Vector Magnitude 35 196 G BC 109 7 52 6 DC 198 2531 G DC 215 936 G MAX X Y and Z Channels as 3 Separate Gaussmeters 213 524 6 DC ri 3 867 G RAS 17 374 kG PE This is a 3 channel gaussmeter It can be used as 3 separate gaussmeters a 2 axis and single channel gaussmeter or a 3 axis gaussmeter The Model 460 configured as 3 separate gaussmeters The Model 460 configured as 2 separate gaussmeters The Model 460 configured as a 3 axis gaussmeter Figure 1 2 Various Model 460 Probe Configurations C 460 1 2 eps Introduction 1 3 1 2 SPECIFICATIONS General Measurement Number of Inputs 3 Update Rate up to 4 readings per second on display up to 14 readings per second with IEEE 488 interface Measurement Modes DC RMS Peak Probe Compatibility Standard multi axis and custom probes Probe Features Linearity Correction Temperature Correction Lake Shore Model 460 Gaussmeter User s Manual Auto Probe Zero Differential Reading Vector Magnitude Measurement Features Auto Range Max Hold Relative Mode Filter Probe Connector 15 pin D style DC Measurement DC Display Resolution 5 digits with filter 4 digits without filter
63. 7 Refer to Chapter 4 for information on remote operation via IEEE 488 Serial DEFINITION OF FRONT PANEL CONTROLS This paragraph provides a description of the front panel controls on the Model 460 The front panel consists of two major sections a description of the 25 front panel keys in Paragraph 3 1 1 anda description of the front panel display in Paragraph 3 1 2 Front panel navigation is described in Paragraph 3 1 3 Turning channels on and off is described in Paragraph 3 1 5 Finally the various Vector Magnitude settings are described in Paragraph 3 1 5 Front Panel Keypad Definitions The keys on the front panel are defined as follows Note the following are abbreviated descriptions of each key A more detailed description of each function is provided in subsequent paragraphs Selects Channel X Once pressed selection of any subsequent channel specific functions relative alarm range etc will affect Channel X Press and hold to turn the channel off Refer to Paragraph 3 1 3 X Selects Channel Y Once pressed selection of any subsequent channel specific functions will affect Channel Y Press and hold to turn the channel off Refer to Paragraph 3 1 3 Selects Channel Z Once pressed selection of any subsequent channel specific functions will affect Channel Z Press and hold to turn the channel off Refer to Paragraph 3 1 3 Selects Vector Magnitude Once pressed selection of any subsequent specific functions will affect
64. A 1904 VG 440 125 dia MNA 1908 VG 820 125 72 005 HST 2 Figure 5 8 Definition of Lake Shore Axial Probes Accessories amp Probes 5 9 Lake Shore Model 460 Gaussmeter User s Manual FLEXIBLE iii PROBES m a A Re Cable ie 6 6 feet 0 125 0 020 0 a 0 030 dia i 2 5 This table is for L 3 inches and S 0 375 inch Corrected Temperature Coefficient Acti Accuracy Operating maximum Model No W A Le KA l Pes of Temperature 0 25 to wenn 3E03 VH 0 09 G C 0 015 C E 135 0 025 0 125 GC 30 kG EE MFT wee VG 0 13 G C 0 005 C 0 005 0 15 to approx ae 30KG 0 Cto MFT wen VH Tubing 0 50 to T5 C MFT 2903 VJ H 0 09 G C 0 015 C can 0 085 0 020 0 065 0 030 30 kG dia MIR prox EH 0 13 G C 0 005 C Flexible a am Tubing HSE 1 Cep 0 09 GI C 0 015 C 0 045 0 150 amp Epoxy DC 1010 0 Cto 0 050 TR 1 75 C max approx Fiber 400HZ Iwer 5 0 15 to 0 13 GPC 0 005 C glass 30 kG Flexible_Transverse eps Figure 5 9 Definition of Lake Shore Flexible Transverse Probes FLEXIBLE AXIAL PROBE Cable Length 6 6 feet 0 36 0 030 dia 0 125 0 020 Active Stem Frequency Corrected Operating Temperature Coefficient max Model No L A Reg Material Ranae Accuracy Temperature 9 of Reading Range Calibration 15 0 025 0 125 0 040 dia Flexible DC 10 to 0 25
65. Address Gauss Tesla Gauss Alarm Keypad Not Locked Alarm Trigger Outside Keypad Setting Channel X Analog Out Default Local Remote Local Analog Out Source x Lock Code 123 Audible Alarm On Max Hold Off Auto Range Off Peak RMS RMS Baud 300 Range Highest Range For Probe 4 Brightness Relative Off Display X Y Z On Vector On Sleep Off Fast Data Mode Off Temp Compensation On Field Compensation On Terminators CR LF Filter Off Vector Source XYZ Filter Number 8 3 16 SPECIAL FUNCTIONS The Model 460 Gaussmeter has some interesting special functions used with the various computer interfaces Fast Data Acquisition Mode is discussed in Paragraph 3 16 1 Analog Output Control Mode in Paragraph 3 16 2 And finally Sleep mode in Paragraph 3 16 3 3 16 1 Fast Data Acquisition Mode In normal operation the instrument updates the display computer interfaces and the corrected analog output at a rate of 4 readings per second A Fast Data Mode has been included to increase the data rate when operating with either the IEEE 488 or Serial Interface While the corrected analog output update rate does correspond to the Fast Data Mode the front panel display will not operate in this mode Use the FAST command over one of the computer interfaces to activate this mode When in Fast Data Mode the user will see the following front panel display Fast Data Mode Without display overhead the instrument can take 18 XYZ readings each second with V
66. Changing IEEE 488 Interface Parametere 4 2 4 1 2 IEEE 488 Command Structure 4 2 4 1 2 1 Bus Control COMM ue E 4 2 4 1 2 2 Common Commands 3 ccs0hi ei tebe Hilda e teo e eo e e Ena i e EE Aa Ea aaite 4 3 4 1 2 3 Device Specific COMMANAS ececeeecececeeceneeteteeeeaeeteseeseaeeteaeeeeaeeseaeeseaeeseaeeeeaeeseaeeseaeeseeeeeaeete 4 3 Table of Contents Lake Shore Model 460 Gaussmeter User s Manual TABLE OF CONTENTS Continued Chapter Paragraph Title 4 1 2 4 Message Strings ea a pa a eae aaa a ae aaaea edd be deci Peds adaa e a aaea ended 4 1 3 Status ReGisters nran reana ra EE E ete 4 1 3 1 Status Byte Register and Service Request Register 4 1 3 2 Standard Event Status Register and Standard Event Status Enable Register A 4 4 4 1 4 IEEE Interface Example Programs cccesccceeesseeeeeeneeeseneeeeeeeneeeeeenaeeesenaeeeeseeeeesenaeeesenaeeeeneneeeeeed 4 5 4 1 4 1 IEEE 488 Interface Board Installation for Visual Basic Program eseeeeseeeeeeneeeeeeeneeerenaes 4 5 4 1 4 2 Visual Basic IEEE 488 Interface Program Getup 4 7 4 1 4 3 IEEE 488 Interface Board Installation for Quick Basic Program 4 10 4 1 4 4 QUICK Basie Progra EE 4 10 4 1 4 5 Program Operation tued dint tans nu ne lei feel evo ei a 4 13 4 1 5 Troubleshooting finissi dae ck eer Zosen d gerode a ced a cepa eee pas E EE ee 4 13 4 2 S rial Interface Overview cac4 Msi Bawendi adenine ann ae 4 14 4 2 1 Physical GOnnection te ere era ENEE EE
67. DS CMDS TERMS PRINT 1 CMDS Send command to instrument IF INSTR CMDS lt gt 0 THEN Test for query RS If query read response N 0 Clr return string and count WHILE N lt TIMEOUT AND INSTR RSS TERMS 0 Wait for response INS INPUTS LOC 1 1 Get one character at a time IF INS THEN N N 1 ELSE N 0 Add 1 to timeout if no chr RSS RSS INS Add next chr to string WEND Get chrs until terminators IF RSS lt gt THEN See if return string is empty RS MIDS RS 1 INSTR RS TERMS 1 Strip off terminators PRINT RESPONSE RSS IT Print response to query ELSE PRINT NO RESPONSE No response to query END IF END IF Get next command GOTO LOOP1 4 20 Remote Operation Lake Shore Model 460 Gaussmeter User s Manual 4 2 7 3 Program Operation Once either program is running try the following commands and observe the response of the instrument Input from the user is shown in bold and terminators are added by the program The word term indicates the required terminators included with the response RESPONSE ENTER COMMAND IDN RESPONSE ENTER COMMAND FIELD RESPONSE RESPONSE RESPONSE 12 345 term ENTER COMMAND FIELDM k term ENTER COMMAND RANGE 0 ENTER COMMAND RANGE O term ENTER COMMAND RANGE 0 RANGE O term Identifi
68. E High Sensitivity Probe UHS Ultra High Sensitivity Probe Usable Full Scale Ranges Vs Probe Type Type HST 1 HST 2 HSE 1 UHS 1 300 G 300 G 30G 300 mG Usable 3kG 3kG 300G 3G Ranges 30kG 30kG 3kG 30G 300 kG 30 kG r _ Is Active Sensing Length W 3 125 Cable Length A 6 6 feet To Center of Active Volume Model No w T A L Frequency Type Range MLA 5006 HJ 0 25 0 5 2 2 5 7 DC 10 to JuHs 1 400 Hz Figure 5 3 Definition of Lake Shore Gamma Probe Accessories amp Probes GAMMA PROBE Small variations in or low values of large volume magnetic fields such as that of the Earth or fringe fields around large solenoids can be measured with these ultra high sensitivity probes Resolutions of several gammas 105 gauss to tens of gammas are available depending on the mating gaussmeter Application is optimum when fields are homogeneous over lengths greater than 1 foot The active sensing length of the gamma probe is 3 125 inches Corrected inj Temperature Coefficient Operatin Accuracy Pp g Maximum of Temperature Calibration Reading Range 1 mG C 0 02 C 0 C to 75 C 0 5 to 2 gauss Gamma eps 5 5 Lake Shore Model 460 Gaussmeter User s Manual 2 amp 3 AXIS PROBES 3 Axis Probe gt 2 Axis Probe lt 3 in gt lt Ii gt j 3 25 in l l GO Was aan g
69. Event Status Register supplies various conditions of the Model 460 STANDARD EVENT STATUS REGISTER FORMAT Bi ae ET E ENEE Weighting 128 64 32 16e 8 4 2 1 Bit Name Bits 2 and 6 are not used The user will only be interrupted with the reports of this register if the bits have been enabled in the Standard Event Status Enable Register and if bit 5 of the Service Request Enable Register has been set Remote Operation Lake Shore Model 460 Gaussmeter User s Manual Standard Event Status Register and Standard Event Status Enable Register Continued 4 1 4 1 The Standard Event Status Enable Register allows the user to enable any of the Standard Event Status Register reports The Standard Event Status Enable command ESE sets the Standard Event Status Enable Register bits If a bit of this register is set then that function is enabled To set a bit send the command ESE with the bit weighting for each bit you want to be set added together See the ESE command discussion for further details The Standard Event Status Enable Query ESE reads the Standard Event Status Enable Register ESR reads the Standard Event Status Register Once this register has been read all of the bits are reset to zero Power On PON Bit 7 Set to indicate an instrument off on transition Command Error CME Bit 5 If bit 5 is set a command error has been detected since the last reading This means that the instrument coul
70. For best results the instrument and probe should warm up for at least 5 minutes before zeroing the probe and at least 30 minutes for rated accuracy The probe and the zero gauss chamber should be at the same temperature The user must consider all the possible contributors to the accuracy of the reading Both the probe and gaussmeter have accuracy specifications that may impact the actual reading The probe should be zeroed before making critical measurements The zero probe function is used to null cancel out the zero offset of the probe or small magnetic fields It is normally used in conjunction with the zero gauss chamber but may also be used with an open probe registering the local earth magnetic field Users wishing to cancel out large magnetic fields should use the Relative function Refer to Paragraph 3 9 Probe temperature can also affect readings Refer to the two separate temperature coefficients listed on the specification sheet The High Stability HST probes exhibit a low temperature coefficient of gain due to the inherent thermal stability of the materials used in its construction NOTE The following discussion relates to the use of single axis probes Three axis probes are already set at right angles and therefore do not exhibit these angle induced errors When using single axis probes readings are dependent on the angle of the sensor Hall sensor in relation to the magnetic field Maximum output occurs when the flux vector i
71. J08 VG 8 0 125 max 0 005 Steg MMT 618 VG 18 0 125 gea a 30 kG MNT 4E02 VG 2 0 125 onge 0 150 xc MNT 4E04 VG 4 0 125 max 0 005 ee F 0 25 dia 0 210 Stainless 400 Hz 2 to 1 5K to METZIOPWN Bato 0 010 0 050 HST me 350K Figure 5 5 Definition of Lake Shore Robust Brass Stem Transverse Probes Brass_Transverse eps Accessories amp Probes 5 7 Lake Shore Model 460 Gaussmeter User s Manual TRANSVERSE PROBES Cable length 6 6 feet 0 36 0 030 dia i Corrected Op Temperature Model No L T W A p a a Type Accuracy Temp Coefficient Max ea ateria ange es ee Calibration MMT 6J02 VH 2 0 125 MMT 6J04 VH 4 0 125 HSE 1 0 25 to 30 kG MMT 6J18 VH 18 0 125 j DC MNT 4E02 VH 2 0 125 9 945 0 150 MNT 4E04 VH 4 0 125 max 0 005 Fa wii o 061 0 180 MMT 6J08 VH 8 0 125 Aen 0 005 MMT 6J02 VG 2 0 125 mr MMT 6J04 VG 4 0 125 0 061 0 180 MMT 6J08 VG 8 0 125 max 0 005 0 15 e MMT 6J18 VG 18 0 125 HsT 21 to 0 005 E 30 kG D MNT 4E02 VG 2 0 125 9 o45 0 150 be MNT 4E04 VG 4 0 125 max 0 005 a 0 25 dia 0 210 Stainless 400 Hz 42 to 15Kto 0 010 WEI 002050 mm Lamm II vm 350K per C Transverse eps Figure 5 6 Definition of Lake Shore Transverse Probes TANGENTIAL PROBE ee a D e Active Area 0 015 0 005 Cable length 6 6 f
72. MMAND FIELDM Field multiplier query Instrument will return a string with the field units multiplier Blank indicated gauss k indicates kilo gauss etc RESPONSE k term ENTER COMMAND RANGE 0 Range command Instrument will change the field range to the highest setting No response will be sent ENTER COMMAND RANGE Range query Instrument will return a string with the present range setting RESPONSE O term The following are additional notes on using either IEEE 488 Interface program e Ifyou enter a correctly spelled query without a nothing will be returned Incorrectly spelled commands and queries are ignored Commands and queries and should have a space separating the command and associated parameters e Leading zeros and zeros following a decimal point are not needed in a command string but are sent in response to a query A leading is not required but a leading is required 4 1 5 Troubleshooting New Installation Check instrument address Always send terminators Send entire message string at one time including terminators Send only one simple command at a time until communication is established Be sure to spell commands correctly and use proper syntax Attempt both Talk and Listen functions If one works but not the other the hardware connection is working so look at syntax terminators and command format 7 If only one message is received
73. Model 4001 RJ 11 Cable Assembly Wiring Details DB 25 CONNECTOR NOT USED Thisconfiguraion isfor a customersupplied computer with DB25 serial interface connedor configured as DCE If the interface is DTE a Null Modem Adapter is required to exchangethe transmit TxD and receive RxD lines RECEPTACLE C 460 6 7 eps Figure 6 7 Model 4002 RJ 11 to DB 25 Adapter Wiring Details DE 9 CONNECTOR NOT USED Thisconfiguraion isfor a customersupplied computer with DE Qserial interface connedor configured as DCE If the interface is DTE a Null Modem Adapte is required to exchangethe transmit TxD and receive RxD lines RJ 11 RECEPTACLE C 460 6 8 eps Figure 6 8 Model 4003 RJ 11 to DE 9 Adapter Wiring Details 6 6 Service Lake Shore Model 460 Gaussmeter User s Manual 6 7 OPERATING SOFTWARE EPROM REPLACEMENT The operating software for the Model 460 is contained on one Erasable Programmable Read Only Memory EPROM Integrated Circuit IC The EPROM is numbered U36 and located just behind the microprocessor IC U31 The EPROM also has a label on top identifying the software version and date see Figure 6 9 Use the procedure below to replace the operating software EPROM WARNING To avoid potentially lethal shocks turn off the instrument and disconnect it from the AC power line before performing this procedure 1 Set power switch to Off and disconnect power cord from rear of unit 2 If at
74. ODEL 460 To hookup a Hall generator you must use the Lake Shore Model MCBL 6 or 20 Cable Assembly The cable has a DA 15 connector on one end and four leads on the other The Hall generator is a 4 lead device The 4 leads are labeled vc Red Ic Black or Green VH Blue and NH Yellow corresponding to the 4 leads on all the Hall generators The Model 460 has an input impedance of 420 Therefore the actual sensitivity at the gaussmeter input will be less than the value given with the Hall generator due to drop in the leads and cable This fact is important because a sensitivity value is supposed to be loaded into the cable PROM to set calibration We recommend that the customer always check accuracy against a reference field rather than use the sensitivity value sent with the bare Hall generator Because Lake Shore has no control of the conditions beyond the cable the customer must accept responsibility for accuracy and compatibility Finally Manganin wire is not usually acceptable for cryogenic installations The resistance of Manganin wire is often too high In cryogenic applications Hall generators are normally connected using twisted pairs of copper wire such as 34 gauge Teflon insulated There are two reasons for this 1 The gaussmeter current source is normally limited in compliance voltage The Model 460 should not drive a load Hall generator Wires in cryostat and probe cable greater than 50 In fact for best perform
75. PIB Address Secondary GPIB Address Terminate Read on EOS Set EOI with EOS on Writes Type of compare on EOS Send EOI at end of Write System Controller Assert REN when SC Enable Auto Serial Polling Enable CIC Protocol National Instruments Primary GPIB Address Secondary GPIB Address Timeout setting Serial Poll Timeout Terminate Read on EOS Set EOI with EOS on Writes Type of compare on EOS EOS byte Send EOI at end of Write Enable Repeat Addressing Fl Help F6 Reset Value F9 Esc Return to Map Ctl PgUp PgDn Next Prev Board GPIBO Configuration DEV12 Configuration GPIB PC2 2A Ver 2 1 Select the primary GPIB address by using the left and right arrow keys This address is used to compute the talk and listen addresses which identify the board or device on the GPIB Valid primary addresses range from 0 to 30 00H to 1EH Adding 32 to the primary address forms the Listen Address LA Adding 64 to the primary address forms the Talk Address TA EXAMPLE Selecting a primary address of 10 yields the following 10 32 42 10 64 74 Listen address Talk address GPIB PC2 2A Ver 2 1 Select the primary GPIB address by using the left and right arrow keys This address is used to compute the talk and listen addresses which identify the board or device on the GPIB Valid primary addresses range from 0 to 30 00H to 1EH Adding 32 to the primary addre
76. PIB Settings Resources View devices by type View devices by co m Computer KR AT GPIB TNT Plug and Play 9 Zi CDROM 19 Disk drives MISA PnP Serial Number O04D7FA0 E S Display adapters H 6 Floppy disk controllers Interface Name m Termination Methods ze Hard disk controllers leen gt E Send EOI at end of Write Keyboard H Monitor GPIB Address H Terminate Read on EOS SZ Mouse Primary P i National Instruments GPIB Interfaces p z M Set EOI with EOS on Write AT GPIB TNT Plug and Play I 8 bit EOS Compare Network adapters Secondary E Ports COM amp LPT 10 EOS Byt NONE D Byte H System devices 1 0 Timeout 10sec S Properties Refresh Remove IV System Controller OK Cancel Figure 4 1 GPIB Setting Configuration System Properties General Device Manager Hardware Profiles Performance I View devices by type i Be National Instruments GPIB Interfaces Properties 20 x E Computer General Device Templates CDROM H E Disk drives LA National Instruments GPIB Interfaces E o Display adapters Floppy disk controllers 4 Hard disk controllers 8 Keyboard BI Monitor A Mouse 4510 Jee National Instruments GPIB Interface e BI Network adapters DEV 12 Attributes A Ports COM am
77. Paragraph 4 1 4 5 16 Press Enter or select the Send button with the mouse to send command 17 Type Exit and press Enter to quit 4 8 Remote Operation Lake Shore Model 460 Gaussmeter User s Manual Table 4 2 Visual Basic IEEE 488 Interface Program Public gSend As Boolean Global used for Send button state Private Sub cmdSend_ Click gSend True End Sub Routine to handle Send button press Set Flag to True Private Sub Form Load Dim strReturn As String Dim term As String Dim strCommand As String Dim intDevice As Integer frmIEEE Show term Chr 13 amp Chr 10 strReturn Call ibdev 0 12 0 T10s 1 amp H140A intDevice Call ibconfig intDevice ibcREADDR 1 Main code section Used to return response Terminators Data string sent to instrument Device number used with IEEE Show main window Terminators are lt CR gt lt LF gt Clear return string Initialize the IEEE device Setup Repeat Addressing Do Do Wait loop DoEvents Give up processor to other events Loop Until gSend True Loop until Send button pressed gSend False Set Flag as False strCommand frmIEEE txtCommand Text Get Command strReturn Clear response display strCommand UCase strCommand Set all characters to upper case If strCommand EXIT Then Get out on EXIT End End If Call ibwrt intDevice strCommand amp term Send command to instrument If ibsta And EERR Then
78. Select With A Audi bl e 0n Off Use the A or W keys to cycle between audible alarm on or off Press Enter to accept the new value or Escape to step to the next function while retaining the old setting Audible is a global setting and applies to all channels The Model 460 will then go to the next display Select With af Alarm I nsi de Out si de Setting Channel zs Use the A or W keys to cycle between the alarm triggered inside or outside alarm setpoints Examples of both inside and outside are given in the following paragraphs Press Enter to accept the changes or Escape to exit the function while retaining the old settings All alarm functions are also available over the IEEE 488 and Serial Interfaces Operation 3 13 Lake Shore Model 460 Gaussmeter User s Manual Alarm Set and Alarm On Off Continued 3 14 One important point to remember is that the alarm setpoints are absolute unsigned i e only the magnitude of the field reading is used Therefore once alarm points are specified any reading whether positive or negative will trigger the alarm The following example details operation with the Alarm Outside setting For example if the reading is to be centered on 1 kG with the high alarm point at 1 5 kG and the low alarm point at 0 5 kG the following diagram illustrates when the alarm would be on or off Alarm Alarm Alarm Alarm Alarm On Off On Off On 3 kG 2 kG 1
79. System of Units or Syst me International d Unit s SI was promulgated in 1960 by the Eleventh General Conference on Weights and Measures For definition spelling and protocols see Reference 3 for a short convenient guide interpolation table A table listing the output and sensitivity of a sensor at regular or defined points which may be different from the points at which calibration data was taken intrinsic coercivity The magnetic field strength H required to reduce the magnetization M or intrinsic induction in a magnetic material to zero intrinsic induction The contribution of the magnetic material Bj to the total magnetic induction B Bi B po H SI Bi B H cgs isolated neutral system A system that has no intentional connection to ground except through indicating measuring or protective devices of very high impedance Kelvin K The unit of temperature on the Kelvin Scale It is one of the base units of SI The word degree and its symbol are omitted from this unit See Temperature Scale for conversions Kelvin Scale The Kelvin Thermodynamic Temperature Scale is the basis for all international scales including ITS 90 It is fixed at 2 points the absolute zero of temperature 0 K and the triple point of water 273 16 K the equilibrium temperature that pure water reaches in the presence of ice and its own vapor line regulation The maximum steady state amount that the output voltage or current will
80. User s Manual Model 460 3 Channel Gaussmeter nal Lake Shore CRYOTRONICS Lake Shore Cryotronics Inc 575 McCorkle Blvd Westerville Ohio 43082 8888 USA Internet Addresses sales lakeshore com service lakeshore com Visit Our Website www lakeshore com Fax 614 891 1392 Telephone 614 891 2243 Methods and apparatus disclosed and described herein have been developed solely on company funds of Lake Shore Cryotronics Inc No government or other contractual support or relationship whatsoever has existed which in any way affects or mitigates proprietary rights of Lake Shore Cryotronics Inc in these developments Methods and apparatus disclosed herein may be subject to U S Patents existing or applied for Lake Shore Cryotronics Inc reserves the right to add improve modify or withdraw functions design modifications or products at any time without notice Lake Shore shall not be liable for errors contained herein or for incidental or consequential damages in connection with furnishing performance or use of this material Rev 2 7 P N 119 012 9 March 2015 10 11 12 13 Lake Shore Model 460 Gaussmeter User s Manual LIMITED WARRANTY STATEMENT WARRANTY PERIOD THREE 3 YEARS Lake Shore warrants that products manufactured by Lake Shore the Product will be free from defects in materials and workmanship for three years from the date of Purchaser s physical receipt of the Product the Warranty Period
81. W keys to cycle through the choices of 300 1200 or 9600 Baud Press Enter to accept the new number or Escape to keep the existing setting and return to the normal display 3 16 Operation 3 12 3 13 Lake Shore Model 460 Gaussmeter User s Manual DISPLAY The Display key permits the user to set the illumination level of the front panel vacuum fluorescent display Pressing the Display key brings up the following display Select With A Brightness d Press the A or W keys to cycle through the choices of 0 to 7 where 0 is the dimmest and the 7 is the brightest display The default setting is 4 Press the Enter key to accept the new number or the Escape key to keep the existing setting and return to the normal display It is recommended that the brightness be kept as low as comfortably readable ANALOG OUT There are two types of analog outputs available on the rear panel of the Model 460 They are the Corrected and Monitor Analog Outputs A single corrected analog output is provided whose source is user definable and three monitor outputs are provided one for each channel The corrected and monitor outputs use BNC connectors with the center conductor carrying the signal and the outer portion the ground To use the corrected analog output in control mode refer to Paragraph 3 16 2 3 13 1 Corrected Analog Out The Corrected Analog Output is a DC value proportional to the displayed field The displayed field reading may b
82. after the probe is attached and power restored to the unit then the channel is probably turned OFF Refer to Paragraph 3 1 3 to turn the channel ON For best results warm up the instrument and probe for at least 5 minutes before zeroing the probe and at least 30 minutes for rated accuracy The probe and the zero gauss chamber should be at the same temperature Operation Lake Shore Model 460 Gaussmeter User s Manual 3 17 2 Probe Handling Although every attempt has been made to make the probes as sturdy as possible the probes are still fragile This is especially true for the exposed sensor tip of some probes Care should be taken during measurements that no pressure is placed on the tip of the probe The probe should only be held in place by securing at the handle The probe stem should never have force applied Any strain on the sensor may alter the probe calibration and excessive force may destroy the Hall generator CAUTION Care must be exercised when handling the probe The tip of the probe is very fragile Stressing the Hall sensor can alter its calibration Any excess force can easily break the sensor Broken sensors are not repairable Avoid repeated flexing of the stem of a flexible probe As a rule the stem should not be bent more than 45 from the base See Figure 3 5 Force should never be applied to the tip of the probe On all probes do not pinch or allow cables to be struck by any heavy or sharp objects Although damaged
83. agraph 6 3 2 Check fuse drawer window for proper voltage setting If incorrect refer to Paragraph 6 4 3 Ensure power switch is off O CAUTION The probe must be connected to the rear of the unit before applying power to the gaussmeter Damage to the probe may occur if connected with power on 4 Plug in the DA 15 probe connector to PROBE INPUT Use thumbscrews to tighten connector to unit 5 Connect and check all other rear panel connections ANALOG OUTPUTS and IEEE 488 or SERIAL I O before applying power to the unit 6 Plug line cord into receptacle Installation Lake Shore Model 460 Gaussmeter User s Manual Initial Setup And System Checkout Procedure Continued 7 Turn power switch on I The front panel display turns on and briefly displays the following message Lake Shore 468 Field Monitor 8 The normal gaussmeter display appears similar to below B kG BC BR kG BC B kG BC HRZ kG aide NOTE For best results the instrument and probe should warm up for at least 5 minutes before zeroing the probe and at least 30 minutes for rated accuracy The probe and the zero gauss chamber should be at the same temperature NOTE Some Lake Shore probes come with a clear plastic sleeve to protect the probe tip when not in use The sleeve slides up and down the probe cable To place the probe in the zero gauss chamber slide the protective sleeve back exposing the probe tip before
84. al driving electric field When exposed to a magnetic field these moving charged particles experience a force perpendicular to both the velocity and magnetic field vectors This force causes the charging of the edges of the conductor one side positive with respect to the other This edge charging sets up an electric field which exerts a force on the moving electrons equal and opposite to that caused by the magnetic field related Lorentz force The voltage potential across the width of the conductor is called the Hall voltage This Hall voltage can be utilized in practice by attaching two electrical contacts to the sides of the conductor The Hall voltage can be given by the expression V4 YgB sin 0 where V Hall voltage mV Yg Magnetic sensitivity mV kG at a fixed current B Magnetic field flux density kilogauss Angle between magnetic flux vector and the plane of Hall generator As can be seen from the formula above the Hall voltage varies with the angle of the sensed magnetic field reaching a maximum when the field is perpendicular to the plane of the Hall generator ACTIVE AREA The Hall generator assembly contains the sheet of semiconductor material to which the four contacts are made This entity is normally called a Hall plate The Hall plate is in its simplest form a rectangular shape of fixed length width and thickness Due to the shorting effect of the current supply contacts most of the sensitivity to ma
85. ambient temperature The error is specified as an amount of change usually in percent for every one degree change in ambient temperature tesla T The SI unit for magnetic flux density B 1 tesla 104 gauss thermal emf An electromotive force arising from a difference in temperature at two points along a circuit as in the Seebeck effect tolerance The range between allowable maximum and minimum values turns N One complete loop of wire Underwriters Laboratories UL An independent laboratory that establishes standards for commercial and industrial products unit magnetic pole A pole with a strength such that when it is placed 1 cm away from a like pole the force between the two is 1 dyne vector A quantity that has both magnitude and direction and whose components transform from one coordinate system to another in the same manner as the components of a displacement Also known as a polar vector volt V The difference of electric potential between two points of a conductor carrying a constant current of one ampere when the power dissipated between these points is equal to one watt volt ampere VA The SI unit of apparent power The volt ampere is the apparent power at the points of entry of a single phase two wire system when the product of the RMS value in amperes of the current by the RMS value in volts of the voltage is equal to one volt second v s A voltage of 1 volt V present at the input of a fluxmeter for 1
86. ance the load should be less than 30 Q 2 Because the Model 460 input impedance is 420 Q there is a voltage drop due to lead resistance in series with the gaussmeter input The Lake Shore Hall generator sensitivity given on the data sheet is basically with no lead resistance See Figure C 4 The gaussmeter needs input sensitivity between 0 5 to 1 5 mV kG HST or 5 0 and 15 mV kG HSE at its input Reable Host Gi aed pen Circuit Sensitivity Gaussmeter Input Reable Poust Sensitivity at Gaussmeter input is e ges Reable Lake Shore Model Reust Customer reduced by the lead input voltage divider MCBL 6 Cable Assembly Supplied Leads C 460 C 4 eps Figure C 4 Hall Generator Input Impedance Hall Generators Lake Shore Model 460 Gaussmeter User s Manual C5 0 SPECIFICATIONS This section covers three types of Hall generators available from Lake Shore HGCA amp HGCT Series Cryogenic Hall generators Figures C 5 and C 6 with specifications Table C 1 HGA Series Axial Hall generators Figures C 5 and C 7 with specifications Table C 2 and HGT Series Transverse Hall generators Figures C 8 thru C 10 with specifications Table C 3 i 10 in min d s d 0 20 in E lameten 1 li CLXXX SS KE EE ee een R L 0 105 el Ke 0 20 in diameter C 460 C 5 eps Figure C 5 Axial Hall Generator HGA 3010 HGA 3030 and HGCA 3020 Dimensions 0 63 in gt 10 in min 0 180 in Lead Length
87. annot be seen felt or heard Service 6 1 6 2 1 6 2 2 6 3 6 2 Lake Shore Model 460 Gaussmeter User s Manual Identification of Electrostatic Discharge Sensitive Components The following are various industry symbols used to label components as ESDS H A EZ Handling Electrostatic Discharge Sensitive Components Observe all precautions necessary to prevent damage to ESDS components before attempting installation Bring the device and everything that contacts it to ground potential by providing a conductive surface and discharge paths As a minimum observe these precautions 1 De energize or disconnect all power and signal sources and loads used with unit 2 Place unit on a grounded conductive work surface 3 Ground technician through a conductive wrist strap or other device using 1 MQ series resistor to protect operator 4 Ground any tools such as soldering equipment that will contact the unit Contact with operator s hands provides a sufficient ground for tools that are otherwise electrically isolated 5 Place ESDS devices and assemblies removed from a unit on a conductive work surface or in a conductive container An operator inserting or removing a device or assembly from a container must maintain contact with a conductive portion of the container Use only plastic bags approved for storage of ESD material 6 Do not handle ESDS devices unnecessarily or remove from the packages until actually used or tested
88. aragraph 6 5 1 PN DESCRIPTION si Input Analog Signal No Connection No Connection ITEMP ITEMP No Connection No Connection lc Input Analog Signal Ground DA Connedor View looking at rear panel No Connection Digital Ground 5 Volts Power Output To Probe EEPROM EE CLK Output To Probe EEPROM EE DATA Serial Input From Probe EEPROM lc Figure 6 2 PROBE INPUT Connector Details 7 2 3 PROBE INPUT 4 5 6 7 8 9 C 460 6 2 eps CHAHHEL X AHALOG OUT Corrected DESCRIPTION 1 Analog Output Center Conductor 2 Ground Connector Shell AHALOG OUT Monitor Monitor Analog Outs repeated for Channels Y and Z C 460 6 3 eps Figure 6 3 ANALOG OUT Corrected and Monitor BNC Connector Details SERIAL LO PIN DESCRIPTION Serial In RxD 1234656 Serial In RxD Serial Ground Serial Ground Serial Out TxD Serial Out TxD RJ 11 Receptacle C 460 6 4 eps Figure 6 4 SERIAL UO Connector Details Service Lake Shore Model 460 Gaussmeter User s Manual 6 5 1 IEEE 488 INTERFACE CONNECTOR Connect to the IEEE 488 Interface connector on the Model 460 rear with cables specified in the IEEE 488 1978 standard document The cable has 24 conductors with an outer shield The connectors are 24 way Amphenol 57 Series or equivalent with piggyback receptacles to allow daisy chaining in multiple device systems The connectors are secured in the receptacles b
89. area for each sensor is defined as the portion of the Hall plate where the majority of magnetic sensitivity occurs See Figures 5 1 and 5 2 and refer to the following table for typical values Probe Type Active Area Distance From Tip of Probe 4 2 mm 0 164 in 2 Axis Axial By Sensor 0 51 mm 0 020 in diameter 2 Axis Transverse Bx Sensor 0 76 mm 0 30 in diameter 5 9 mm 0 234 in 3 Axis for all 3 axes 0 76 mm 0 30 in diameter 1 8 mm 0 070 in The probe tip is very fragile protect it from any abrasions blows bends stress or excessive temperatures Take care during measurements to place no pressure on the probe tip Hold the probe in place only by securing the handle Never apply force to the probe stem Any strain on the Phenolic may alter the probe calibration and excessive force may destroy the Hall sensors Both 2 amp 3 axis probes provide more consistent readings in a low gradient magnetic field The higher the gradient the higher the error caused by the Hall sensors not occupying the same point in space Connect the probes to their respective connectors on the Model 460 rear panel Note that neither the Y nor Z probe functions if the X channel is turned off or disconnected Each connector is marked with the channel axis designation A single channel probe may be connected to the Z channel while a 2 axis probe uses the X and Y channels Transverse x active area 0 76 m
90. ator Specifications Description Instrumentation quality axial low Instrumentation quality axial phenolic temperature coefficient phenolic package package Maximum continuous current non 300 mA 300 mA heat sinked Magnetic sensitivity I nominal 0 55 to 1 05 mV kG 6 0 to 10 0 MV kG control current Maximum linearity error sensitivity 1 RDG 30 to 30 kG 0 30 RDG 10 to 10 kG versus field 1 5 RDG 100 to 100 kG 1 25 RDG 30 to 30 kG Zero field offset voltage Ip nominal 50 uV max 75 uV max control current Operating temperature range 40 to 100 C 40 to 100 C Mean temperature coefficient of 0 005 C max 0 04 C max magnetic sensitivity Mean temperature coefficient of offset 0 4 uV C max 0 3 uV C max lc nominal control current Mean temperature coefficient of 0 15 C approx 0 18 C approx resistance Leads 34 AWG copper with poly nylon 34 AWG copper with poly nylon insulation insulation C 6 Hall Generators Lake Shore Model 460 Gaussmeter User s Manual Table C 3 Transverse Hall Generator Specifications HGT 1010 HGT 3010 HGT 3030 Description General purpose Instrumentation quality Instrumentation quality transverse 0 020 inch thick transverse low temperature transverse ceramic package coefficient ceramic package Active area approximate 0 040 inch diameter circle 0 040 inch diameter circle 0 040 inch diameter c
91. be provided before Lake Shore can attempt any repair Instrument model and serial number User s name company address and phone number Malfunction symptoms Description of system Returned Goods Authorization RGA number Hr Ze G If possible the original packing material should be retained for reshipment If not available consult Lake Shore for shipping and packing instructions Because of their fragility Lake Shore probes are shipped in special cardboard and foam boxes These boxes should be retained for storage of probes while the gaussmeter is not in use The same box can be used to return probes to Lake Shore for recalibration or repair Installation 2 1 Lake Shore Model 460 Gaussmeter User s Manual 2 3 REAR PANEL DEFINITION This paragraph provides a description of the Model 460 rear panel connections The rear panel consists of the line input assembly IEEE 488 Interface Connector Serial UO Connector Probe Input Connectors and Corrected and Monitor Analog Output BNCs This paragraph is provided for information only Please read the entire paragraph then proceed to Paragraph 2 7 for the initial setup and system checkout procedure Rear panel connector pin out details are provided in Chapter 6 Service CAUTION Verify AC Line Voltage shown in the fuse holder window is appropriate for the intended AC power input Also remove and verify the proper fuse is installed before plugging in and turning on the instrume
92. can easily break the Hall generator Broken Hall generators are not repairable Hall Generators are very fragile and require delicate handling The ceramic substrate used to produce the Hall Generator is very brittle Use the leads to move the Hall generator Do not handle the substrate The strength of the lead to substrate bond is about 7 ounces so avoid tension on the leads and especially avoid bending them close to the substrate The Hall Generator is also susceptible to bending and thermal stresses POLARITY If the control current enters the red lead with 1 connected to the positive terminal of the current supply and the magnetic field direction is as shown in Figure C 2 a positive Hall voltage will be generated at the blue lead V Reversing either the current or the magnetic field will reverse the output voltage LEAD CONFIGURATIONS All Hall generators except Models HGCA 3020 and HGCT 3020 have 34 AWG solid copper with poly nylon insulation and have the same lead configuration as follows Red ze Green le Blue WH Clear WvH Input iControl Current outputcHall vottage The Model HGCA 3020 and HGCT 3020 Hall generators have 34 AWG stranded copper with Teflon insulation and have the following lead configuration Red Sec E Input CC ontrol C ur rent Blue W H ellon AH Output Hall wota ge HALL GENERATOR GENERIC HOOKUP The Hall voltage leads may also be connected directly to a rea
93. can send instrument setup commands and query field reading data The maximum reading rate of the instrument can be achieved using the IEEE 488 interface Nearly every function of the instrument front panel can be performed over the computer interface Two types of analog voltage outputs are also included with the Model 460 The single Corrected Analog Output is a DC voltage proportional to the display reading It is generated using a D A converter programmed at the instrument update rate Available software error correction and vector calculations can be used when generating the corrected output voltage Three Monitor outputs are real time analog voltages proportional to the field at each input These outputs do not have the advantage of software correction but are much faster than the Corrected output with the full DC to 400 Hertz bandwidth Operation The Model 460 has several software features intended to make multi axis field measurements more convenient A bright four line vacuum fluorescent display and full function keypad provide easy access to these features and give meaningful feedback X Y and Z Axis with Vector Magnitude 46 663 G DC 166 812 6 BC 768 661 G DC 775 292 G Ave The Model 460 can display each axis simultaneously plus Vector Magnitude XYZ X2 Y2 Z2 1 Introduction Lake Shore Model 460 Gaussmeter User s Manual Product Description Continued X and Y Axis with Differential Reading 165 625
94. cation query Instrument will return a string identifying itself LSCI MODEL460 0 070199 term Field reading query Instrument will return a string with the present field reading Field multiplier query Instrument will return a string with the field units multiplier Blank indicated gauss k indicates kilo gauss etc Range command Instrument will change the field range to the highest setting No response will be sent Range query Instrument will return a string with the present range setting Range command followed by range query Instrument will change range to highest setting then return a string with the present range setting The following are additional notes on using either Serial Interface program e Ifyou enter a correctly spelled query without a nothing will be returned Incorrectly spelled commands and queries are ignored Commands and queries and should have a space separating the command and associated parameters e Leading zeros and zeros following a decimal point are not needed in a command string but they will be sent in response to a query A leading is not required but a leading is required Remote Operation 4 21 4 2 8 4 3 4 22 Lake Shore Model 460 Gaussmeter User s Manual Trouble Shooting New Installation 8 Check instrument baud rate 9 Make sure transmit TD signal line from the instrument is routed to receive RD on the computer and vice versa Use a nu
95. change as the result of a specified change in input line voltage usually for a step change between 105 125 or 210 250 volts unless otherwise specified line of flux An imaginary line in a magnetic field of force whose tangent at any point gives the direction of the field at that point the lines are spaced so that the number through a unit area perpendicular to the field represents the intensity of the field Also know as a Maxwell in the cgs system of units line voltage The RMS voltage of the primary power source to an instrument Glossary of Terminology A 3 Lake Shore Model 460 Gaussmeter User s Manual load regulation A steady state decrease of the value of the specified variable resulting from a specified increase in load generally from no load to full load unless otherwise specified M Symbol for magnetization See magnetization magnetic air gap The air space or non magnetic portion of a magnetic circuit magnetic field strength H The magnetizing force generated by currents and magnetic poles For most applications the magnetic field strength can be thought of as the applied field generated for example by a superconducting magnet The magnetic field strength is not a property of materials Measure in SI units of A m or cgs units of oersted magnetic flux density B Also referred to as magnetic induction This is the net magnetic response of a medium to an applied field H The relationship is given by the following equatio
96. d controller command is RST Configure Event Status Enable Register ESE lt bit weighting gt term nnn term Each bit is assigned a bit weighting and represents the enable disable mask of the corresponding event flag bit in the Standard Event Status Register To enable an event flag bit send the command ESE with the sum of the bit weighting for each desired bit Refer to Paragraph 4 1 3 2 for a list of event flags To enable event flags 0 3 4 and 7 send the command ESE 143 term 143 is the sum of the bit weighting for each bit Bit Bit Weighting Event Name 0 1 OPC 3 8 DDE 4 16 EXE 7 128 PON 143 Event Status Enable Register Query KESE term lt bit weighting gt nnn term Refer to Paragraph 4 1 3 2 for a list of event flags Standard Event Status Register Query ESR term lt bit weighting gt nnn term The integer returned represents the sum of the bit weighting of the event flag bits in the Standard Event Status Register Refer to Paragraph 4 1 3 1 for a list of event flags Identification Query IDN term lt manufacturer gt lt model gt 0 lt date gt term aaaa aaaaaaaa n mmddyy lt manufacture gt Manufacturer ID lt model gt Instrument model number 0 Indicates no serial number included lt date gt Instrument firmware revision date LSCI MODEL460 0 020399 Remote Operation Lake Shore Model 460 Gaussmeter User s Manual Common Commands Continued OPC Input Remarks
97. d not interpret the command due to a syntax error an unrecognized header unrecognized terminators or an unsupported command Execution Error EXE Bit 4 If bit 4 the EXE bit is set an execution error has been detected This occurs when the instrument is instructed to do something not within its capabilities Device Dependent Error DDE Bit 3 A device dependent error has been detected if the DDE bit is set The actual device dependent error can be found by executing the various device dependent queries Query Error QYE Bit 2 The QYE bit indicates a query error It occurs rarely and involves loss of data because the output queue is full Operation Complete OPC Bit 0 This bit is generated in response to the OPC common command It indicates when the Model 460 has completed all selected pending operations IEEE Interface Example Programs Two BASIC programs are included to illustrate the IEEE 488 communication functions of the instrument The first program was written in Visual Basic Refer to Paragraph 4 1 4 1 for instructions on how to setup the program The Visual Basic code is provided in Table 4 2 The second program is written in Quick Basic Refer to Paragraph 4 1 4 3 for instructions on how to setup the program The Quick Basic code is provided in Table 4 3 Finally a description of operation common to both programs is provided in Paragraph 4 1 4 5 While the hardware and software required to produce and implemen
98. d on the gaussmeter One peak occurs as the probe enters the magnet a second and greater peak is observed as the midpoint is reached and a third smaller peak is read as the probe leaves the magnet The calibration point is the largest reading in the midpoint area Its amplitude will be approximately twice that of the readings that occur where the probe enters or leaves the magnet 4 7 cm dia k 1 845 0 32 dia min working space Transverse 0 062 gap MRT 062 200 within 1 of nominal value MRT 062 500 within 1 of nominal value Axial 0 312 diameter working space MRT 062 1K within 0 5 of nominal value MRA 312 2K within 1 of nominal value MRT 062 2K within 0 5 of nominal value MRA 312 1K within 1 of nominal value MRT 062 5K within 0 5 of nominal value 3 96cm 5 6 cm 1 56 O D k Gei 0 79 cm 0 31 dia min working space Axial 0 312 diameter working space Center line of magnet MRA 312 100 within 1 of nominal value is center of gap MRA 312 200 within 1 of nominal value Transverse 0 062 gap MRA 312 500 within 1 of nominal value MRT 062 10K within 0 5 of nominal value P 460 5 14 bmp Figure 5 14 Lake Shore Reference Magnets Accessories amp Probes 5 13 Lake Shore Model 460 Gaussmeter User s Manual NOTE Use care to ensure the Zero Gauss Chamber does not become magnetized Using a magnetized chamber to zero a probe can lead to erroneous field readings It is a good practice
99. deg Eege EENS SEENEN C 1 C1 0 EE C 1 C2 0 Theory ee EE EE C 1 C3 0 Hall Generator Generic Hookup A C 3 C4 0 Using a Hall Generator with the Model 460 C 4 C5 0 ee TEE C 5 C6 0 HALE GAL EXE Program eege EEN deed dee yin eis owes tive a Sa C 8 ii Table of Contents Figure No 1 1 1 2 2 1 2 2 2 3 3 1 3 2 3 3 3 4 3 5 3 6 3 7 4 1 4 2 4 3 4 4 5 1 5 2 5 3 5 4 5 5 5 6 5 7 5 8 5 9 5 10 5 11 5 12 5 13 5 14 5 15 5 16 5 17 5 18 5 19 6 1 6 2 6 3 6 4 6 5 6 6 6 7 6 8 6 9 C 1 C2 C 3 CA C 5 C 6 C7 Lake Shore Model 460 Gaussmeter User s Manual LIST OF ILLUSTRATIONS Title Page Model 460 Front Panel t2 30 testi a ie Me ele OR ha ee a hes 1 1 Various Model 460 Probe Configurations ecccccceeeeeeeeeeeeneeeeeeeeaeeseaeeeeaeeseaeeeeaeeseaeeeeaeeseeeseaeeseieeeeieeeeaes 1 3 Model 460 Rear EE 2 2 Line INpUL ASSOMDIY dee Eed NEEN EE Ae ead ee 2 3 Model MCBL XX User Programmable Cable ACceseon 2 4 Model 460 Front NEE 3 1 Front Panel EspleTietotgn sde serene tees te SE dE Edge a Ee 3 3 Display Filter Response Examples ccsccccceseececesesceeceseneeeeeseeenessaeeeseseneeecaaeaeseseqaeeseseeeesseeeeesenenseesescees 3 10 Monitor Analog Output Frequency Response sseesseeseesiesiesiteettetitetinttttttttttttttnstrnsttatinattnntnntn neunten nenne 3 20 Maximum Flexible Probe Bend Radius nnnnneessennnneesseennnrnnnressttnnntesstrtrnnnttetttnnnnesstnnnnnnnsetnnnennn nnen ee nnn 3 25
100. del 460 error messages that may be seen during normal operation OL Field range has been exceeded Refer to Paragraph 3 4 to change Range No Probe No probe attached to the instrument at power up Power the instrument off attach a probe and power it on again Locked Keypad is locked to prevent accidental parameter changes To unlock keypad refer to Paragraph 3 14 Error 1 NOVRAM memory is physically malfunctioning Contact Lake Shore service for repair Error2 NOVRAM memory is not initialized properly Memory can be reinitialized as described in Paragraph 3 15 This operation will not restore calibration data that may have been corrupted Instrument calibration should be checked after any Error 2 condition Contact Lake Shore service for repair or calibration If the keyboard locks up hold Escape for about 20 seconds to reset the Model 460 to factory defaults The gaussmeter then requires the user to re enter setpoints and zero the probe Service Lake Shore Model 460 Gaussmeter User s Manual APPENDIX A GLOSSARY OF TERMINOLOGY accuracy The degree of correctness with which a measured value agrees with the true value electronic accuracy The accuracy of an instrument independent of the sensor sensor accuracy The accuracy of a temperature sensor and its associated calibration or its ability to match a standard curve algorithm A set of well defined rules for the solution of a problem in a finite number of steps Am
101. dout instrument such as a high impedance voltmeter or can be attached to electronic circuitry for amplification or conditioning Device signal levels will be in the range of microvolts to hundreds of millivolts In this case a separate precision current source Lake Shore Model 120CS or equivalent is necessary See Figure C 3 CAUTION The four Hall generator leads connect to four points on a sheet of semiconductor material having different potentials No two leads can be connected together without adversely affecting operation Therefore the current source and the output indicator cannot have acommon connection but must be isolated from each other One the other but not both may be grounded CAUTION Do not exceed the maximum continuous control current given in the specifications The Hall generator input is not isolated from its output In fact impedance levels on the order of the input resistance are all that generally exist between the two ports To prevent erroneous current paths which can cause large error voltages the current supply must be isolated from the output display or the down stream electronics Hall Generators C 3 C4 0 CA Lake Shore Model 460 Gaussmeter User s Manual to Hall Generator Model 120CS VH Current Source Digital Voltmeter Load resistor required for optimum linearity if specified C 460 C 3 eps Figure C 3 Typical Hall Generator Hookup USING A HALL GENERATOR WITH THE M
102. e 15 2 meters 50 feet MPEC 100 Probe Extension Cable 30 5 meters 100 feet Included with purchase of gaussmeter 5 3 LAKE SHORE STANDARD PROBES There are several types of Lake Shore Model 460 probes available 2 and 3 Axis Axial Gamma Tangential and Transverse each named for its Hall sensor orientation Because the Model 460 covers such a wide magnetic field range 0 01 mG to 300 kG three probe ranges are available High Stability HST High Sensitivity HSE and Ultra High Sensitivity UHS Please consult the factory for availability of probe types not detailed in this section Information on Hall generators is presented in Appendix C of this manual 5 3 1 Probe Selection Criteria Some guidelines are provided below to aid in the selection of a probe for you application T 2 Choose a probe to match the application Do not buy more accuracy field range or fragility than is actually necessary The thinner a probe the more fragile it is Try to avoid the temptation to select an easily damaged probe based on a possible but not probable future application For instance avoid using an exposed device probe such as a Model MFT 3E03 or MNA 1904 type for general field measurements Once a stem or sensor has been damaged the probe is not repairable Metal enclosed probes such as the Model MMT 6J08 and MMA 2508 types offer the greatest amount of protection to the Hall sensor and therefore are the most rugged t
103. e Compensation eeeeeceeeeeeneeeeeeeeeeeeteeeteaeeseaeeeeaeeeeaeeseaeeseaeeseeeseeeeeneeeeaes 3 11 3 8 GAUSSATOS EE 3 11 3 9 Relative Set and Relative On Off AAA 3 12 3 10 Alert Set ang Alarm IDN bes Geer Hed castes ih cian een Een ees ere tea Ee 3 13 3 11 Local andi Interlace isese iivreceereed Ash aae Erara e E Ea eae een tte eon cae ae 3 16 3 12 DISPLAY sects ce TE E ees Shee edn OE Ae Se aac an te outta SMEG as E A eG ee cade 3 17 3 13 Analog Quits EER E A cks esac teed cecil est scPacaa EE 3 17 3 13 1 Corrected Analog OUt iiss ocsi TEEN iE dt ce ue edebte edi ea ieie iri Eio aei 3 17 3 13 2 Monitor Analog TEE 3 20 3 14 Locking and Unlocking the Keyboard 3 21 3 15 Factory Defaut Set OS geess seed eege e 3 22 3 16 Special FUNCHONS sisri pee eias i ai tote lad A SENON eech EES 3 22 3 16 1 Fast Data Acquisition Mode iiin e aaa a reae a aa Sue 3 22 3 16 2 Analog Output Control Mode 3 23 3 16 3 Sleep e EE 3 23 3 17 Eelere ET EE 3 24 3 17 1 Changing Probes de dich cent Bin vile blk el ee ied Eii AE 3 24 3 17 2 Probe aNd in WEE 3 25 3 17 3 Probe Polary teeraa tet sth ctr tects edb ate shen a a due tevaues oudeyiek eave a a dueneean ie 3 26 3 17 4 Probe Accuracy Considerations A 3 27 4 COMPUTER INTERFACE OPERATION ccsseesseeesseeesseeenseeeseeeenseeesseeeeseeeaseeeaseeeeseeeeseeaseeeeseeeaseeeeseeeseeeeesneeeeees 4 1 4 0 GENERAL wend oh A eee eed Se ee eel 4 1 4 1 IEEE 488 IN TEREAG eg gece edel geet ei dE eh ee 4 1 4 1 1
104. e corrected for probe non linearity zero offset and temperature This output is not a real time signal but is updated at the same rate as the display 4 times per second The output range of the corrected analog output is 3 volts A jumper is located inside the Model 460 that can change the corrected analog output to 10 volts This jumper will be set at the factory per the customer s original request The jumper can be changed in the field but may shift the calibration slightly Help in locating the jumper JMP2 is provided in Figure 6 9 The following examples assume a 3 volt setting NOTE Only one channel source may be chosen at a time by the user The default range of the Corrected output is 3 volts equals full scale for the selected range For the example below the 3 kG range was selected 0KG Ronit 3 kG 2 kG 1 kG 1 KG 2 KG 3 KG Output E ER 1V 1V 2V 3V Voltage 7 T ay a F 2 To select the default range press the Analog Out key and observe the following display Select With af Anal o3 Out Aber User Operation 3 17 Lake Shore Model 460 Gaussmeter User s Manual Corrected Analog Out Continued Press the Analog Out A or V key to cycle the arrow to Def Default Press the Enter key You will then see the channel selection display as follows Select With A Analod Out Source a Press the A or W key to cycle the analog output source from channel X Y Z or Vector In
105. e in textbox on main form Reset holding string Reset timeout counter Private Sub Timerl_ Timer frmSerial Timerl Enabled False End Sub Routine to handle Timer interrupt Turn off timer Remote Operation 4 19 Lake Shore Model 460 Gaussmeter User s Manual 4 2 7 2 Quick Basic Serial Interface Program Setup The serial interface program Table 4 7 works with QuickBasic 4 0 4 5 or Qbasic on an IBM PC or compatible running DOS or in a DOS window with a serial interface It uses the COM1 communication port at 9600 Baud Use the following procedure to develop the Serial Interface Program in Quick Basic Start the Basic program Enter the program exactly as presented in Table 4 7 Adjust the Com port and Baud rate in the program as necessary Lengthen the TIMEOUT count if necessary Save the program Run the program Type a command query as described in Paragraph 4 2 7 3 Type EXIT to quit the program Si NO Ro NS Table 4 7 Quick Basic Serial Interface Program CLS Clear screen PRINT SERIAL COMMUNICATION PROGRAM PRINT TIMEOUT 2000 Read timeout may need more BAUDS 9600 TERMS CHR 13 CHRS 10 Terminators are lt CR gt lt LF gt OPEN COM1 BAUDS 0 7 1 RS FOR RANDOM AS 1 LEN 256 LINE INPUT ENTER COMMAND or EXIT CMDS Get command from keyboard CMD UCASES CMDS Change input to upper case IF CMDS EXIT THEN CLOSE 1 END Get out on Exit CM
106. e last byte allowing for variable length data transmissions End Or Identify EOI Status Query END term lt state gt term n Refer to command for description Fast Data Mode Command FAST lt state gt term n lt state gt 0 Off 1 On Via the IEEE 488 Interface Fast Data Mode reaches data rates up to18 readings per second with Vector Magnitude turned off or 14 readings per second with Vector Magnitude turned on If using the Serial Interface a maximum of 14 readings per second is possible at 9600 baud With either interface there is a corresponding increase in corrected analog output The front panel display does not function in this mode Refer to Paragraph 3 16 1 Fast Data Mode Query FAST term lt state gt term n Refer to command for description Front Panel Key Pressed Query KEY term lt state gt term n lt state gt 0 No 1 Yes Queries the gaussmeter to check for any front panel key pressed since the last query over the remote interface Front Panel Keyboard Lock Command LOCK lt state gt term n lt state gt 0 Unlocked 1 Locked Locks out all front panel entries except pressing the Alarm key to silence alarms Refer to Paragraph 3 14 Use the CODE command to set the lock code Front Panel Keyboard Lock Query LOCK term lt state gt term n Refer to command for description Remote Operation Lake Shore Model 460 Gaussmeter User s Manual Interface Commands Co
107. eading Multiplier Query MAXRM term lt multiplier gt term a lt multiplier gt u micro 10 m milli 10 blank unity k kilo 10 Used with MAXR query Peak RMS Field Reading Command PRMS lt state gt term n lt state gt 0 RMS 1 Peak Configures unit for RMS or Peak measurements RMS or Peak is selected after ACDC is set to AC Refer to Paragraph 3 5 Peak RMS Field Reading Query PRMS term lt state gt term n Refer to command for description Manual Range Command RANGE lt range gt term n lt range gt 0 first range highest 1 second range 2 third range 3 fourth range lowest Range depends on type of probe installed There are four ranges possible for each probe Refer to Paragraph 3 4 Manual Range Query RANGE term lt range gt term n Refer to command for description Relative Mode Command REL lt state gt term n lt state gt 0 Off 1 On Works with the RELR RELRM RELS and RELSM commands Remote operation is slightly different from front panel operation described in Paragraph 3 9 From the front panel the current reading is captured as the setpoint when Relative is turned on However when activated by remote command the initial relative setpoint is zero The RELS command is used to enter a setpoint Remote Operation 4 37 Lake Shore Model 460 Gaussmeter User s Manual Device Specific Commands Continued REL Input
108. eading Query FIELD term lt field value gt term tnnn nn lt field value gt Returns sign 4 or 5 digits and places decimal point appropriate to range Use FIELDM to determine units multiplier and UNITS to determine gauss or tesla units Magnetic Field Reading Multiplier Query FIELDM term lt multiplier gt term a lt multiplier gt u micro 10 m milli 10 blank unity k kilo 10 Used with FIELD query Display Filter Command FILT lt state gt term n lt state gt 0 Off 1 On Quiets the display reading by a degree depending on the points FNUM and window FWIN settings Refer to Paragraph 3 6 Display Filter Query FILT term lt state gt term n Refer to command for description Display Filter Points Command FNUM lt points gt term nn lt points gt Integer from 2 thru 64 Sets filter points Numbers 2 thru 8 produce a linear filter response Numbers 9 thru 64 produce an exponential filter response In general the higher the number the longer the display settle time Refer to Paragraph 3 6 Display Filter Points Query FNUM term lt points gt term nn Refer to command for description 4 35 Lake Shore Model 460 Gaussmeter User s Manual Device Specific Commands Continued FWIN Input Format Remarks FWIN Input Returned Format MAX Input Format Remarks MAX Input Returned Format MAXC Input Remarks
109. ector Magnitude turned off or 14 XYZ and Vector Magnitude readings each second with Vector Magnitude turned on An efficiently written IEEE 488 program can return all 18 XYZ or 14 XYZV readings using the ALLF command to query the field measurement data without slowing the instrument down Use the ONOFF command to turn the vector magnitude on or off When the Vector Magnitude is turned off the instrument will still respond to the ALLF command with four readings X Y Z and V but the fourth reading will consist of meaningless data that should be ignored The Serial Interface is capable of 14 readings per second in the Fast Data Mode When using either interface never try to read faster than the update rate Specific information on command syntax is provided in Paragraph 5 3 3 22 Operation Lake Shore Model 460 Gaussmeter User s Manual Fast Data Acquisition Mode Continued 3 16 2 3 16 3 NOTE When Fast Data Mode is activated the following Model 460 functions are disabled Relative Max Hold Alarms and Autorange NOTE Temperature compensation if applicable is based on the last temperature reading prior to activation of the FAST DATA MODE The temperature is not updated during the use of FAST DATA The additional overhead associated with Serial Communication will slow the instrument communicating over the Serial Interface to a maximum of 14 readings per second at 9600 Baud When using the Serial Interface never try to read
110. eet 0 36 0 030 dia E W e Corrected Op Temperature Cem L i W A Con GE Ze Type Accuracy Temp Coefficient Max E of rdg Range Zero MNTAN 1 5 0 125 0 38 0 030 0 020 dia DC 10 to 0 25 0 Cto Plasti i HSE 1 0 1 G C 0 05 C DQ02 TH 0 125 0 005 approx 400 Hz se to20kG 75 C Tangential eps Figure 5 7 Definition of Lake Shore Tangential Probe 5 8 Accessories amp Probes Lake Shore Model 460 Gaussmeter User s Manual AXIAL PROBES lt B Active Corrected Temp Coefficient Max Type Accuracy ge Reading Calibration MMA 0602 TH 20 125 MMA 0604 TH 4 0 125 al DC 0 25 MMA 0608 TH 8 0 125 e 1 to E i lt V 0 003 MMA 0618 TH 18 0 125 0 0207 iii SS et dia Alum HST 2 MMA 0802 UH 2 0 125 approx een D to 20 kG MMA 0804 UH 4 0 125 MNA 1902 VH_ 2 0 125 9 497 MNA 1904 VH_ 440 125 dia MNA 1908 VH_ 820 125 0005 MMA 1802 VH_ 2 0 063 wg MMA 1808 VH 840 125 gia HSE 1 o per C MMA 1818 VH 18 0 25 0 016 MMA 1836 VH 36 0 25 N MMA 2502 VH 2 0 063 0 25 dia gou A MMA 0808 UH 8 0 125 0 005 1 to MMA 1808 WL 8 0 125 100 kG MMA 2536 WL 36 0 25 0 25 dia dere 0 006 pe 0 25 dal 0 025 Stainless 2 to 11 5Kto 0 010 A 2560 WN 0 50 60 0 50 0 005 0 005 100kG 350K per C Axial eps 0 005 per C MNA 1902 VG 240 125 9497 approx 400 Hz MN
111. efer component replacement and internal adjustments to qualified maintenance personnel Do not replace components with power cable connected To avoid injuries always disconnect power and discharge circuits before touching them Do Not Substitute Parts Or Modify Instrument Do not install substitute parts or perform any unauthorized modification to the instrument Return the instrument to an authorized Lake Shore Cryotronics Inc representative for service and repair to ensure that safety features are maintained 1 4 SAFETY SYMBOLS Directourfent powerline Equipment protected throughout by Alternating current power line double insulation or reinforced insulation equivalent to Class II of IEC 536 see Annex H 4 Caution High voltages danger of l electric shock Background color Earth ground terminal Yellow Symbol and outline Black Caution or Warning See Alternating or direct current power line Three phase alternating current power line Protective conductor terminal instrument documentation Background color Yellow Symbol Frame or chassis terminal and outline Black On supply O O A Off supply Introduction 1 5 1 6 Lake Shore Model 460 Gaussmeter User s Manual This Page Intentionally Left Blank Introduction 2 0 2 1 2 2 Lake Shore Model 460 Gaussmeter User s Manual CHAPTER 2 INSTALLATION GENERAL This chapter provides general Model 460 installation i
112. el 460 Gaussmeter User s Manual 4 0 4 1 CHAPTER 4 COMPUTER INTERFACE OPERATION GENERAL This chapter provides operational instructions for the computer interface for the Lake Shore Model 460 Gaussmeter Either of the two computer interfaces provided with the Model 460 permit remote operation The first is the IEEE 488 Interface described in Paragraph 4 1 The second is the Serial Interface described in Paragraph 4 2 The two interfaces share a common set of commands detailed in Paragraph 4 3 Only one of the interfaces can be used at a time IEEE 488 INTERFACE The IEEE 488 Interface is an instrumentation bus with hardware and programming standards that simplify instrument interfacing The Model 460 IEEE 488 Interface complies with the IEEE 488 2 1987 standard and incorporates its functional electrical and mechanical specifications unless otherwise specified in this manual All instruments on the interface bus perform one or more of the interface functions of TALKER LISTENER or BUS CONTROLLER A TALKER transmits data onto the bus to other devices A LISTENER receives data from other devices through the bus The BUS CONTROLLER designates to the devices on the bus which function to perform The Model 460 performs the functions of TALKER and LISTENER but cannot be a BUS CONTROLLER The BUS CONTROLLER is the digital computer which tells the Model 460 which functions to perform Below are Model 460 IEEE 488 interface capabilities e SH
113. el Ap LE Setting Channel zs Use the A org arrow keys to toggle the channel on or off Press the Enter key to select a new setting or press the Escape key or wait for the time out to exit and retain the old setting If the channel is turned off the line in the display will be blank and the excitation current will be turned off to the X Y or Z channels Do no turn off the X channel when using a multi axis probe If no probe is attached to a channel the corresponding display will be blank regardless if the channel is turned on or off Operation 3 2 Lake Shore Model 460 Gaussmeter User s Manual Vector Source In addition to turning the Vector Magnitude display on or off the source of the Vector display must also be selected Press and hold the Vector Magnitude key until the display reads Channel ON then press the Enter key You will see the following display Select With A Vector Source AYZ Use the A org arrow keys to toggle the vector source between XYZ XY XZ YZ and X Y Press the Enter key to select a new setting or press the Escape key or wait for the timeout to exit and retain the old setting The vector source will be shown in the normal display However if Max Hold is selected for the vector magnitude display the identifier MAX will appear in the normal display instead of the vector source The following is a mathematical description of the components that comprise the Vector Magnitude
114. ent CH o 5in diameter diameter 2 Axis Probe Corrected Model No Stem Frequency Type Accuracy Material Range of RDG 0 25 to 20 kG 0 5 from 20 to 30 kG MMY 1818 UH 18 0 25 MMY 1836 UH 36 0 25 MMZ 2502 UH 2 125 0 125 MMZ 2504 UH 4 125 0 125 Alum in MMY 1802 UH 2 0 125 MMY 1808 UH 8 0 125 Kuminura DETA 1 ygea Hz to 400 Hz 3 Axis Probe MMZ 2508 UH 8 125 0 125 0 25 to 20 kG DC and 10 um Hz to 400 Hz 0 5 from 20 to 30 kG E 0 25 in Joen diameter Z 8 s 0 7 0 5 DO 0 18 in square tB x Temperature Coefficient Calibration 0 015 C Operating Temperature Range 10 C 0 09 to 40 C gauss C 0 015 C 0 09 gauss C 2 3_Axis eps Figure 5 4 Definition of Lake Shore 2 and 3 Axis Probes 5 6 Accessories amp Probes Lake Shore Model 460 Gaussmeter User s Manual ROBUST BRASS STEM TRANSVERSE PROBES Cable length 6 6 feet 0 36 0 030 dia Corrected Op Temperate Model No L T W A on each Type Accuracy Temp Coefficient Max rea ateria ange i of rdg Range Calibration MMT 6J02 VH 2 0 125 MMT 6J04 VH 4 0 125 0 061 max MMT 6J08 VH 8 0 125 MMT 6J18 VH 18 0 125 MNT 4E02 VH 2 0 125 9 q45 0 150 MNT 4E04 VH 4 0 125 max 0 005 0 150 0 040 Be dia MMT 6J02 VG 2 40 125 ar ee 0 25 to 30 kG MMT 6J04 VG 4 0 125 0 180 MMT 6
115. ent filter algorithms that result in slightly different settling time computations For filter points from 2 to 8 a linear average is used to get the fastest possible response In this case the filter will settle in the same number of samples as entered For example when set at 8 filter points and updating at 4 readings per second the filter will settle in 2 seconds For filter points from 9 to 64 an exponential algorithm is used to get a smooth response The settling time for a 1 change to full display resolution is approximately the same as the number of filter points in seconds For example a setting of 10 filter points will settle in 10 seconds The difference in linear and exponential response is illustrated in Figure 3 3 The Vector Magnitude display uses filtered component values if in DC mode and the Filter is turned on for each of the component channels is turned on ee epee Exponential Response with Filter Points set to 9 Linear Response with Fitter Points set to 8 Step Change in Magnetic Field Seconds 15 0 10 20 30 40 50 60 Readings C 460 3 3 eps Figure 3 3 Display Filter Response Examples Operation 3 7 3 8 Lake Shore Model 460 Gaussmeter User s Manual FIELD AND TEMPERATURE COMPENSATION Pressing and holding the Filter key for 5 seconds will show the following field and temperature compensation displays NOTE Unless there is a specific reason to the contrary Lake Shore strongly advises cu
116. ent use Lake Shore Cryotronics Inc assumes no liability for Customer failure to comply with these requirements The Model 460 protects the operator and surrounding area from electric shock or burn mechanical hazards excessive temperature and spread of fire from the instrument Environmental conditions outside of the conditions below may pose a hazard to the operator and surrounding area e Temperature 5 C to 40 C e Maximum relative humidity 80 for temperature up to 31 C decreasing linearly to 50 at 40 C e Power supply voltage fluctuations not to exceed 10 of the nominal voltage Ground The Instrument To minimize shock hazard connect the instrument chassis and cabinet to an electrical ground The instrument is equipped with a three conductor AC power cable Plug the power cable into an approved three contact electrical outlet or use a three contact adapter with the grounding wire green firmly connected to an electrical ground safety ground at the power outlet The power jack and mating plug of the power cable meet Underwriters Laboratories UL and International Electrotechnical Commission IEC safety standards Do Not Operate In An Explosive Atmosphere Do not operate the instrument or probes in the presence of flammable gases or fumes Operation of any electrical instrument in such an environment constitutes a definite safety hazard Keep Away From Live Circuits Operating personnel must not remove instrument covers R
117. equest Tells the bus controller that the Model 460 needs interface service A Multiline Command asserts a group of signal lines All devices equipped to implement such commands do so simultaneously upon command transmission These commands transmit with the Attention ATN line asserted low The Model 460 recognizes two Multiline commands LLO Local Lockout Prevents the use of instrument front panel controls DCL Device Clear Clears Model 460 interface activity and puts it into a bus idle state Remote Operation Lake Shore Model 460 Gaussmeter User s Manual Bus Control Commands Continued 4 1 2 2 4 1 2 3 4 1 2 4 Finally Addressed Bus Control Commands are Multiline commands that must include the Model 460 listen address before the instrument responds Only the addressed device responds to these commands The Model 460 recognizes three of the Addressed Bus Control Commands SDC Selective Device Clear The SDC command performs essentially the same function as the DCL command except that only the addressed device responds GTL Go To Local The GTL command is used to remove instruments from the remote mode With some instruments GTL also unlocks front panel controls if they were previously locked out with the LLO command SPE Serial Poll Enable and SPD Serial Poll Disable Serial polling accesses the Service Request Status Byte Register This status register contains important operational informa
118. er of coil center of coil center of coil Coil Resistance Inductance 23 QO 6 3 mH 210 0 36 mH 220 Q 93 mH Maximum Continuous Current 2 A DC or AC RMS Operating Temperature Range 10 to 40 C 50 to 104 F 1 25 WIDE 1 00 HIGH OPENING THRU BOTH SIDES BANANA JACKS CCURRENT INPUT P 460 5 11 bmp Figure 5 11 Model MH 2 5 Helmholtz Coil Accessories amp Probes 5 11 Lake Shore Model 460 Gaussmeter User s Manual Banana Jacks aa Input zs ed e 3 5 _ 5 4 pee BEEN P 460 5 12 bmp P 460 5 13 bmp Figure 5 13 Model MH 12 Helmholtz Coil 5 12 Accessories amp Probes Lake Shore Model 460 Gaussmeter User s Manual 5 5 REFERENCE MAGNETS Magnetic reference standards containing highly stable permanent magnets have been in use for many years The highest quality units are usually shielded from external magnetic effects and use Alnico V or VI magnets for long term stability They are supplied in both transverse flat and axial configurations Typical transverse reference magnets are usually stabilized for use at ambient temperatures between 0 50 C and have nominal temperature coefficients of about 0 02 C Because the temperature coefficient is negative the field strength will be reduced as the temperature rises Since these references are temperature cycled during manufacture their change with temperature is predictable and retraceable they
119. er right hand corner of the display signifying alarm on To turn the alarm off again press the Alarm On Off key The message Alarm Off briefly appears When an alarm condition exists i e the field reading is outside the alarm setpoints the musical note will flash and if turned on the audible alarm will sound Operation Lake Shore Model 460 Gaussmeter User s Manual Alarm Set and Alarm On Off Continued The following example details how the alarm operates in the Alarm Inside setting The alarm inside setup is useful in situations where the user is looking for an indication of a good reading such as incoming inspections For example you may be sorting a number of 1 kG magnets The magnets have an acceptable tolerance of 0 25 kG With the high alarm point set to 1 25 kG and the low alarm point at 0 75 kG the following diagram illustrates when the alarm would be on or off Alarm Alarm Alarm Alarm Alarm Off TT Oon Off TT OH Off 3 kG 2 kG 1 kG 0 kG 1 kG 2 kG 3 kG Example of operation Low Alarm with alarm triggered by e readings INSIDE user Point defined setpoints High Alarm Point To enter this alarm setup push the Alarm Set key The user is asked to enter the High Alarm Point H ob Alarm Poi nt 1 2568 kG Setting Channel a The initial range displayed is the same as the latest probe range To set an alarm in a different range push the Select Range key until the proper range
120. erial specific property defined as the magnetic moment m per unit volume V M m V Measured in SI units as A m and in cgs units as emu cm 1 emu cm 10 A m Since the mass of a sample is generally much easier to determine than the volume magnetization is often alternately expressed as a mass magnetization defined as the moment per unit mass magnetostatic Pertaining to magnetic properties that do not depend upon the motion of magnetic fields mains See line voltage Maxwell Mx A cgs electromagnetic unit of magnetic flux equal to the magnetic flux which produces an electromotive force of 1 abvolt in a circuit of one turn link the flux as the flux is reduced to zero in 1 second at a uniform rate MKSA System of Units A system in which the basic units are the meter kilogram and second and the ampere is a derived unit defined by assigning the magnitude 4x x 107 to the rationalized magnetic constant sometimes called the permeability of space NBS National Bureau of Standards Now referred to as NIST National Institute of Standards and Technology NIST Government agency located in Gaithersburg Maryland and Boulder Colorado that defines measurement standards in the United States See Standards Laboratories for an international listing noise electrical Unwanted electrical signals that produce undesirable effects in circuits of control systems in which they occur normalized sensitivity For resistors signal sensitivi
121. erican Standard Code for Information Exchange ASCII A standard code used in data transmission in which 128 numerals letters symbols and special control codes are represented by a 7 bit binary number as follows JOJON DU A Ww My O w yo rn lt x x lt cjajv aod um 1 Q O ie O 0 O ie 0 1 1 1 1 1 1 1 1 ojo o o ololoj o 7 o o o o o o ojo 9 oj oj o o0 j o 0 o joj 7 O Z IS rlzsieiratleamprpbi o 3 3 x 7 bo alo jajo joja j o o LO e Inte x j lt je j j s lolol N E OY ITAT American Wire Gage AWG Wiring sizes are defined as diameters in inches and millimeters as follows AWG _ Dia In Dia mm AWG _ Dia In Dia mm AWG _ Dia In Dia mm AWG _ Dia In Dia mm 1 0 2893 7 348 11 0 0907 2 304 21 0 0285 0 7230 31 0 0089 0 2268 2 0 2576 6 544 12 0 0808 2 053 22 0 0253 0 6438 32 0 0080 0 2019 3 0 2294 5 827 13 0 0720 1 829 23 0 0226 0 5733 33 0 00708 0 178 4 0 2043 5 189 14 0 0641 1 628 24 0 0207 0 5106 34 0 00630 0 152 5 0 1819 4 621 15 0 0571 1 450 25 0 0179 0 4547 35 0 00561 0 138 6 0 1620 4 115 16 0 0508 1 291 26 0 0159 0 4049 36 0 00500 0 127 7 0 1443 3 665 17 0 0453 1 150 27 0 0142 0 3606 37 0 00445 0 1131 8 0 1285 3 264 18 0 0403 1 024 28 0 0126 0 3211 38 0 00397 0 1007 9 0 1144 2 906 19 0 0359 0 9116 29 0 0113 0 2859 39 0 00353 0 08969
122. ets enoni ee ai Sh as eee eee dee EE EE 5 12 Bi SERVICE EE 6 1 6 0 ELE 6 1 6 1 General Maintenance Precautions eeccccccceeseeeesneeceeeteaeeeeaeeceaeeeeaeeceaeeesaeeseaeeeeaeeseaeeenaeeteaeeesaeetias 6 1 6 2 Electrostatic Dischargey 2 s c diecitectiiines Wl des lasek eile cele 6 1 6 2 1 Identification Of Electrostatic Discharge Sensitive Components ssesssseseesreerrerreererereesrsrresens 6 2 6 2 2 Handling Electrostatic Discharge Sensitive Componerts 6 2 6 3 Line Voltage Selection nivsecken kins eed eed wee Gabe debi neat aie a 6 2 6 4 Fuse Replacement ieren oira aeaa eea cecceshsacedevecusaedesstedisasneeacainatitagiebazecgveihsaiieepasetscastaaasise 6 3 6 5 Rear Panel Connector Definttons AAA 6 4 6 5 1 IEEE 488 Interface Connector eecceceseeeceseaeeceaceseseeeeaeeceaeeseaeeceneeseaeeseseeeeaceseaeeseaeeseaeeseaeereaees 6 5 6 6 Optional Serial Interface Cable And Adapters cece cere eee eeee eee teeeeaeeeaeeeaeseaeteeeseeeeaeeaes 6 6 6 7 Operating Software Eprom Replacement cccceecceeeeeeeeeeeeseeeeeeeeeeeeseeeeseeeeseaeesaeeseaeeeseeeseaeeenaten 6 7 6 8 AAKO ACERT GE 6 8 APPENDIX A GLOSSARY OF TERMINOLOGY cccssessesesseeeeeeeeneeeeeeaeeeeneesseeeeseeeseeeneeesseeeeeeeesseeeeaseesseeeseseeeeneees A 1 APPENDIX B UNITS FOR MAGNETIC PROPERTIES cccssecsseeesseeeeeeeenseeeeeeeeeneeeeeaeeeneeeseeeeneeesseeeenseeseeeeeeseeeseenss B 1 APPENDIX C HALI GENERATORS reese degt eEgeg eege
123. etting Channel jd Pressing the Filter or A or W keys toggles between On and Off Press the Enter key to accept the new setting or the Escape key to leave the setting as is and return to the normal display When the Filter is turned on the user will see two additional displays The first is the Filter Points display and the second is the Filter Window display The default is 8 filter points and a 1 filter window The Filter Points display is shown below Select With at Filter Poirnts B8 Setting Channel jd Operation 3 9 Lake Shore Model 460 Gaussmeter User s Manual Filter Continued 3 10 The filter points tell the instrument how many points to use in the filter algorithm From 2 to 64 points are permitted One point is taken each display update cycle so the filter settling time will depend on update speed and number of samples The second display is for filter window as shown below Select With A Filter Window Hl Setting Channel jd The filter limit window sets a boundary for restarting the filter If a single field reading is different from the filter value by more than the limit specified the instrument will assume the change is intentional and restart the filter at the new reading value This allows the instrument to respond to changing fields much faster than if the filter functioned continually Filter Window can be set from 1 to 10 of the present range The Model 460 uses two differ
124. faster than the update rate Analog Output Control Mode It is sometimes convenient to use the corrected analog output as a control voltage output instead of an analog output proportional to measured field A set of computer interface commands control the digital to analog converter DAC for the corrected analog output One common application is using the output to program an electromagnet power supply By using the analog output the user can avoid purchasing a magnet supply controller and adding a separate interface to their computer The Model 460 software dated 10 1 94 and newer supports this feature Update software for older Model 460s is available at no charge The actual output voltage and voltage resolution depends on an instrument hardware setting In a standard Model 460 the output range of the corrected analog output is 3 volts A jumper is located inside the gaussmeter that can change the corrected analog output to 10 volts This jumper is set at the factory per the customer s original request The jumper can be changed in the field but may shift the calibration slightly See Figure 6 9 to locate jumper JMP2 Output Range 3 volts 10 volts Resolution 0 37mV 1 2 mV Two commands control the corrected analog output via the IEEE 488 or Serial Interface The ANOD command specifies interface control of the output set it to 2 Send this command only once The ANOD query confirms the change This setting will not change if t
125. ge F 460 2 3 eps Figure 2 3 Model MCBL XX User Programmable Cable Accessory CAUTION The Hall Generator should be isolated from all line voltages or voltages referenced to earth ground f not damage to the Model 460 Gaussmeter is almost a certainty Refer to Appendix C for a complete list of compatible Hall generators manufactured by Lake Shore Once connections are made refer to Paragraph C6 0 for instructions on using the Hallcall exe program to store probe parameters in the internal EPROM CORRECTED AND MONITOR ANALOG OUTPUTS Analog outputs are available on Bayonet Nut Connectors BNCs The signal is on the center conductor while the outer casing is for ground All outputs may be used simultaneously The corrected output is not a real time signal but is updated at the same rate as the display The monitor outputs are live analog signals proportional to the magnetic flux density waveform of the respective channel Refer to Paragraph 3 13 for further operational information INITIAL SETUP AND SYSTEM CHECKOUT PROCEDURE This procedure verifies basic unit operation before initial use for measurements CAUTION Check power source for proper voltage before connecting line cord to the Model 460 Check power setting on fuse drawer window Damage may occur if connected to improper voltage 1 Check power source for proper voltage The Model 460 operates with 100 120 220 or 240 5 10 AC input voltage If incorrect refer to Par
126. ge the line voltage selector per instructions in Paragraph 6 3 The fuse must be removed to verify its value refer to the procedure in Paragraph 6 4 Use slow blow fuses of the value specified on back of the instrument Power Cord The Model 460 includes a three conductor power cord Line voltage is present across the outer two conductors The center conductor is a safety ground and connects to the instrument metal chassis For safety plug the cord into a properly grounded three pronged receptacle Power Switch The power switch turns the instrument On and Off and is located in the line input assembly on the instrument rear When Lis raised the instrument is On When O is raised the instrument is Off Line Cord Power Switch Fuse Input O Off I On Drawer N LINE 10 5 Voltage 50 60 Hz 50 VA MAX FUSE DATA 100 120 V 1 0 A 0 25 x 1 25 in T 220 240 V 0 5A 5 x 20 mm T F 460 2 2 eps Figure 2 2 Line Input Assembly PROBE INPUT CONNECTION WARNING Some probes used with the gaussmeter have conductive parts Never probe near exposed live voltage Personal injury and damage to the instrument may result CAUTION Always turn off the instrument before making any rear panel Probe Input connections Lake Shore probes plug into three 15 pin D style connectors on the rear panel Turn the instrument off before attaching a probe Align the probe connector with the rear panel connector and push straight in to avoid bendi
127. gnetic fields is contained in an area approximated by a circle centered in the Hall plate whose diameter is equal to the plate width Thus when the active area is given the circle as described above is the common estimation Hall Generators C 1 Lake Shore Model 460 Gaussmeter User s Manual Ic Red lt Conventional Current F e v x B force on electron VH Clear or Yellow VH Blue High Mobility II V Semiconductor a Indium arsenide b Gallium arsenide wl Ic Green or Black C 460 C 1 eps Figure C 1 Hall Generator Theory C2 2 ORIENTATION Hall generators come in two main configurations axial and transverse Transverse devices are generally thin and rectangular in shape They are applied successfully in magnetic circuit gaps surface measurements and general open field measurements Axial sensors are mostly cylindrical in shape Their applications include ring magnet center bore measurements solenoids surface field detection and general field sensing S berg BESSE Transverse emm B lt lt eS Axial C 460 C 2 eps Figure C 2 Axial and Transverse Configurations C 2 Hall Generators C2 3 C2 4 C2 5 C3 0 Lake Shore Model 460 Gaussmeter User s Manual HANDLING CAUTION Care must be exercised when handling the Hall generator The Hall generator is very fragile Stressing the Hall generator can alter its output Any excess force
128. he instrument is powered off but it can be changed back to normal operation from the front panel The AOCON command sets bipolar output voltage in percent of full scale The setting format of xxx xx allows for a sign and a resolution of 0 01 As a safety precaution this setting always equals zero if the instrument looses power or is turned off The setting cannot be changed from the front panel The AOCON query confirms the change Example Sending AOCON 50 25 sets output to 50 25 of full scale This is 5 025 V for a 10 V output or 1 5075 V for a 3 V output Sleep Mode Sleep mode is provided to allow the user to turn off all three current sources at one time To accomplish this the SLEEP command is issued over one of the computer interfaces SLEEP 0 turns the Sleep Mode on while SLEEP 1 turns Sleep Mode off This command is useful when gathering a sensitive measurement elsewhere in a system where the current sources in the gaussmeter may interfere with the measurement NOTE What the ONOFF command can accomplish for individual channels SLEEP can do for all three channels simultaneously Operation 3 23 3 17 Lake Shore Model 460 Gaussmeter User s Manual PROBE CONSIDERATIONS To avoid damage and for best results during use the probes have a number of handling and accuracy requirements that must be observed Changing probes is discussed in Paragraph 3 17 1 Probe handling is discussed in Paragraph 3 17 2 Probe operation is
129. howing a 0 00008 kG relative reading from the 0 0922 kG captured value The relative feature also interacts with other features When alarm is active the alarm points follow the relative reading Refer to Paragraph 3 10 for further information on setting alarms The Relative and Max Hold functions may be used at the same time In this case the relative reading becomes the maximum deviation from the relative setpoint and the DC is replaced with the MAX indication An example of Relative and Max Hold on at the same time is shown below DDR kG MAK a RB 25 776 kG DC RH 96952 kG DC H 9431 1 kG ad Pressing Max Hold again turns off the maximum hold function returning the relative reading to the display Pressing the Relative On Off key turns off the relative function The Relative Off message is briefly displayed Operation Lake Shore Model 460 Gaussmeter User s Manual Relative Set and Relative On Off Continued 3 10 NOTE The following discussion relates only to a 3 axis configuration where X Y and Z are mutually orthogonal axes The effect that relative has on the Vector Magnitude depends on how the relative function is initiated There are two meaningful ways to use the relative function with the Vector Magnitude The first provides a magnitude of the difference vector while the second provides a difference in magnitude of the field vector Magnitude of Difference Vector If rela
130. ield units the letters DC displaying 4 digits with no filter or 5 digits with the Filter on The DC value is available over the IEEE 488 and Serial Interfaces and both Analog Outputs Operation Lake Shore Model 460 Gaussmeter User s Manual AC DC and Peak RMS Continued 3 6 In AC operation the user must select either RMS or Peak Both meet specified accuracy from 10 to 400 Hz The lowest range for the type probe installed is not available in the AC Peak mode The AC RMS reading is a measurement of true RMS defined as the square root of the average of the square of the field function taken through one period The RMS reading will work on complex waveforms to a crest factor of 7 and DC component will be rejected if it is not large enough to overload the selected range The AC Peak readings can be used in two different applications With Max Hold off the Peak Crest of a periodic symmetrical waveform is measured If the field change at the probe is not well behaved the peak reading will not always show the largest field value In this case look at the monitor output with an oscilloscope to see how the reading relates to the field The Peak reading used with Max Hold on will measure the amplitude of a single peak like a magnetizing pulse It will hold the reading until reset with Max Reset The AC value is available over the IEEE 488 and Serial Interfaces A DC voltage representation of the Peak or RMS display reading is available fro
131. ilo 108 Used with RELS query Remote Operation Lake Shore Model 460 Gaussmeter User s Manual Device Specific Commands Continued UNIT Input Format UNIT Input Returned Format VSRC Input Format Remarks VSRC Input Returned Format Gauss Tesla Units Command UNIT lt unit gt term a lt unit gt G gauss T tesla Refer to Paragraph 3 8 Gauss Tesla Unit Query UNIT term lt unit gt term a Refer to command for description Vector Magnitude Source Command VSRC lt source gt term n lt source gt 1 XYZ 2 XY 3 XZ 4 YZ 5 X Y Sets the source of Vector Magnitude channel calculations Refer to Paragraph 3 1 5 Vector Magnitude Source Query VSRC term lt source gt term n Refer to command for description 4 3 4 Probe Specific Commands FCOMP Input Format Remarks FCOMP Input Returned Format ONOFF Input Format Remarks Field Compensation Command FCOMP lt state gt term n lt state gt 0 Off 1 On Turns set field compensation On or Off If Off probe field compensation table if present is ignored Refer to Paragraph 3 7 Field Compensation Query FCOMP term lt state gt term n Refer to command for description Probe On Off Command ONOFF lt state gt term n lt state gt 0 Off 1 On Sets probe on off status First specify channel X Y or Z with the CHNL command Remote Operation 4
132. in relation to the magnetic field This does not apply to 3 axis probes This and other effects on probe operation are explained in Paragraph 3 17 13 Carefully place probe into reference magnet You may have to hunt around for the maximum reading For this example we are using a 999 1 Gauss Reference Magnet Our reading appeared as follows 9958 kG MAS Assuming we are using a probe attached to the X axis the maximum reading captured was 0 9950 kG which is within the tolerance of the reference magnet The reading will change as the probe moves around but will eventually remain fixed on the highest reading To recapture a new maximum value press the Max Reset key 14 Repeat Steps 12 and 13 for the Y and Z probes if present 15 Once this abbreviated checkout procedure is successfully completed the unit is ready for normal operation Please proceed to Chapter 3 for further operational information 2 6 Installation 3 0 3 1 3 1 1 Lake Shore Model 460 Gaussmeter User s Manual CHAPTER 3 OPERATION GENERAL This chapter describes Model 460 3 Channel Gaussmeter operation The front panel controls are described in Paragraph 3 1 Paragraphs 3 2 thru 3 14 describe the various front panel functions in detail Model 460 default settings are defined in Paragraph 3 15 Special functions available over computer interface are discussed in Paragraph 3 16 Finally probe considerations are presented in Paragraph 3 1
133. ion of this product at the time of shipment are traceable to the United States National Institute of Standards and Technology NIST formerly known as the National Bureau of Standards NBS FIRMWARE LIMITATIONS Lake Shore has worked to ensure that the Model 460 firmware is as free of errors as possible and that the results you obtain from the instrument are accurate and reliable However as with any computer based software the possibility of errors exists In any important research as when using any laboratory equipment results should be carefully examined and rechecked before final conclusions are drawn Neither Lake Shore nor anyone else involved in the creation or production of this firmware can pay for loss of time inconvenience loss of use of the product or property damage caused by this product or its failure to work or any other incidental or consequential damages Use of our product implies that you understand the Lake Shore license agreement and statement of limited warranty FIRMWARE LICENSE AGREEMENT The firmware in this instrument is protected by United States copyright law and international treaty provisions To maintain the warranty the code contained in the firmware must not be modified Any changes made to the code is at the user s risk Lake Shore will assume no responsibility for damage or errors incurred as result of any changes made to the firmware Under the terms of this agreement you may only use the Model 460 firmware
134. iption Serial Interface Baud Rate Command BAUD lt baud gt term n lt baud gt 0 300 1 1200 and 2 9600 baud Refer to Paragraph 3 11 Serial Interface Baud Rate Query BAUD term lt baud gt term n Refer to command for description Front Panel Display Brightness Command BRIGT lt brightness gt term n lt brightness gt 0 dimmest thru 7 brightest Default setting is 4 Refer to Paragraph 3 12 Front Panel Display Brightness Query BRIGT term lt brightness gt term n Refer to command for description Front Panel Keyboard Lock Code Command CODE lt lock code gt term nnn lt lock code gt Enter any three numbers Default 123 Refer to Paragraph 3 14 Front Panel Keyboard Lock Code Query CODE term lt lock code gt term nnn Refer to command for description Remote Operation 4 27 Lake Shore Model 460 Gaussmeter User s Manual Interface Commands Continued END Input Format Remarks END Input Returned Format FAST Input Format Remarks FAST Input Returned Format KEY Input Returned Format Remarks LOCK Input Format Remarks LOCK Input Returned Format 4 28 End Or Identify EOI Status Command END lt state gt term n lt state gt 0 Enabled 1 Disabled Sets the EOI status When enabled the hardware EOI line becomes active with the last byte of a transfer The EOI identifies th
135. ircle input resistance approx Output resistance approx Nominal control current 100 mA 100 mA 100 mA lcn current non heat sinked Magnetic sensitivity l 7 5 to 12 5 mV kG 0 55 to 1 05 mV kG 6 0 to 10 0 mV kG nominal control current Maximum linearity error 1 0 RDG 1 RDG 0 30 RDG sensitivity versus field 10 to 10 kG 30 to 30 kG 10 to 10 kG 1 5 RDG 1 25 RDG 100 to 100 kG 30 to 30 kG Zero field offset voltage Ic 100 uV max Ge uV max 75 uV max nominal control current Operating temperature 40 to 100 C 40 to 100 C 40 to 100 C range Mean temperature 0 08 C max 0 005 C max 0 04 C max coefficient of magnetic sensitivity Mean temperature 1 uV C max 0 4 uV C max 0 3 uV C coefficient of offset Ic nominal control current Mean temperature 0 18 C approx 0 15 C approx 0 18 C approx coefficient of resistance Leads 34 AWG copper with poly 34 AWG copper with poly 34 AWG copper with poly nylon insulation nylon insulation nylon insulation Hall Generators C 7 Lake Shore Model 460 Gaussmeter User s Manual C6 0 HALLCAL EXE PROGRAM The HALLCAL EXE program was developed by Lake Shore Cryotronics Inc to allow the interfacing of customer attached Hall generators to the Model 460 Gaussmeter Please refer to the Software License Agreement behind the title page of this manual This program is provided with the purchase
136. ive a response immediately e Receive the entire response from the instrument including the terminators e Guarantee that no other communication is started during the response or for 50 ms after it completes e Not initiate communication more than 20 times per second Failure to follow these simple rules will result in inability to establish communication with the instrument or intermittent failures in communication Changing Baud Rate To use the Serial Interface you must first set the Baud rate Press Interface key to display the following screen Select With at Baud E 1 96 Press the A or W keys to cycle through the choices of 300 1200 or 9600 Baud The rate selected will have a right pointing arrow gt immediately to the left Press Enter to accept the new number Remote Operation Lake Shore Model 460 Gaussmeter User s Manual 4 2 7 Serial Interface Basic Programs Two BASIC programs are included to illustrate the serial communication functions of the instrument The first program was written in Visual Basic Refer to Paragraph 4 2 7 1 for instructions on how to setup the program The Visual Basic code is provided in Table 4 4 The second program was written in Quick Basic Refer to Paragraph 4 2 7 2 for instructions on how to setup the program The Quick Basic code is provided in Table 4 5 Finally a description of operation common to both programs is provided in Paragraph 4 2 7 3 While the hardware and soft
137. l 460 Serial Interface Connector configured as DCE If the interface is DTE a Null Modem Adapter is required to exchange Transmit and Receive lines The Model 4001 4002 and 4003 are DS options available from Lake Shore Use whichever adapter that matches your computer serial interface connector Pin outs are described in Paragraph 6 6 LSCI Model 4003 RJ 11 to DE 9 Adapter LSCI Model 4001 RJ 11 Cable Assembly To customer supplied computer with DE 9 Serial Interface Connector configured as DTE If the interface is DCE a Null Modem Adapter is required to exchange Transmit and Receive lines _ C 460 4 4 eps Figure 4 4 Serial Interface Adapters Remote Operation 4 2 2 4 2 3 4 2 4 Remote Operation Lake Shore Model 460 Gaussmeter User s Manual Hardware Support The Model 460 interface hardware supports the following features Asynchronous timing is used for the individual bit data within a character This timing requires start and stop bits as part of each character so the transmitter and receiver can resynchronized between each character Half duplex transmission allows the instrument to be either a transmitter or a receiver of data but not at the same time Communication speeds of 300 1200 or 9600 baud are supported The Baud rate is the only interface parameter that can be changed by the user Hardware handshaking is not supported by the instrument Handshaking is often used
138. l Enabled True Do DoEvents Main code section Used to return response Temporary character space Terminators Counter used for Timing out Data string sent to instrument Show main window Terminators are lt CR gt lt LF gt Initialize counter Clear return string Clear holding string Close serial port to change settings Example of Comm 1 Example of 9600 Baud Parity Data Stop Read one character at a time Open port Wait loop Give up processor to other events Loop until Send button pressed Set Flag as false Get Command Clear response display Set all characters to upper case Get out on EXIT Send command to instrument Check to see if query Wait for response Add 1 to timeout if no character Wait for 10 millisecond timer Loop Until frmSerial Timerl Enabled False ZeroCount ZeroCount 1 Else ZeroCount 0 strHold frmSerial MSComm1 Input strReturn strReturn strHold End If Wend If strReturn lt gt Then strReturn Mid strReturn 1 InStr strReturn Else strReturn No Response End If frmSerial txtResponse Text strReturn strHold mn ZeroCount 0 End If Loop End Sub Timeout at 2 seconds Reset timeout for each character Read in one character Add next character to string Get characters until terminators Check if string empty Term 1 Strip terminators Send No Response Put respons
139. ll modem adapter if not 10 Always send terminators 11 Send entire message string at one time including terminators Many terminal emulation programs do not 12 Send only one simple command at a time until communication is established 13 Be sure to spell commands correctly and use proper syntax Old Installation No Longer Working 5 Power instrument off then on again to see if it is a soft failure 6 Power computer off then on again to see if communication port is locked up 7 Verify that baud rate has not been changed on the instrument during a memory reset 8 Check all cable connections Intermittent Lockups 3 Check cable connections and length 4 Increase delay between all commands to 100 ms to make sure instrument is not being over loaded COMMAND SUMMARY This paragraph provides a summary of the IEEE 488 and Serial Interface Commands The summary is divided into four command groups common commands are detailed in Paragraph 4 3 1 interface commands in Paragraph 4 3 2 device specific commands in Paragraph 4 3 3 and probe commands in Paragraph 4 3 4 A summary of all commands is provided in Table 4 8 Command Name Brief Description of Function High Alarm Setpoint Query ALMH term Syntax of what user must input Information returned in response to the query Returned lt field value gt term Format nnn nn Refer to command for description Response format see Key below Remarks Use ALMHM to de
140. ll the values entered along with designated F keys F1 Probe Serial Number ABC123 F2 Probe Type 0 F3 Calibration Constant X XXX F10 Program Probe Esc Exit Program 8 At this time if any of the parameters need to be changed just press the appropriate F key and type in the new value When everything appears correct press F10 to program the probe 9 Ittakes about 20 seconds to program the probe After the probe is programmed press the Esc key to exit the program C 8 Hall Generators
141. ly zeroed Users wishing to cancel large magnetic fields must use the Relative function The zero probe function is not available for the Vector Magnitude display NOTE For best results the instrument and probe should warm up for at least 5 minutes before zeroing the probe and at least 30 minutes for rated accuracy The probe and the zero gauss chamber should be at the same temperature NOTE Some Lake Shore probes are equipped with a clear plastic sleeve intended to protect the tip of the probe when not being used The sleeve is designed to slide up and down the probe cable If you need to place the probe in the zero gauss chamber you must slide the protective sleeve back exposing the tip of the probe before placing the tip in the chamber To zero the probe in the zero gauss chamber first allow the temperature of the probe and chamber to equalize A large temperature discrepancy affects the quality of the calibration Carefully place the probe tip into the chamber Orientation of the probe is not critical Once inserted press the channel key in this case Channel X then press the Zero Probe key and observe the following display Press Enter With Probe At Zero Setting Channel zs Press the Enter key The CALIBRATING message is displayed followed by a return to the normal display Do not move the probe while calibrating The probe is now zeroed For best results periodic zeroing of the probe is recommended Operatio
142. m 0 030 in diameter Axial Y active area ermmm 031MM 0 020 in diameter ke e M EN D I I U 1 A By H U i U U U H CS H U U U U i I Sandan fw x b Dotted line E surrounding the active A A s s Wu l a area indicates the stem l Side view Front view 4 2 mm gt lt 0 164 in Se 1 8 mm 0 070 in NOTE Active area is defined as the portion of the Hall plate where the majority of magnetic sensitivity occurs Figure 5 1 2 Axis Probe Tip Details Accessories amp Probes Lake Shore Model 460 Gaussmeter User s Manual Axial Z active area 0 76 mm 0 030 in diameter a deg aaa I I 2 08 mm 0 082 in I By B be kat 4 Dotted line surrounding the Transverse X amp Y active areas 0 76 mm 0 030 in diameter active area l indicates the stem DEE en mme gt E WEE EE Front view 2 08 mm TR Side view 0 082 in 0 070 in NOTE Active area is defined as the portion of the Hall plate where the majority of magnetic sensitivity occurs Figure 5 2 3 Axis Probe Tip Details 5 3 4 Probe Specifications Terminology used in Figures 5 3 thru 5 10 are defined as follows Definition of Probe Terminology A Distance from tip to center line of active area B Magnetic flux density vector for reading HST High Stability Probe HS
143. m the Corrected Analog Output while a true analog waveform is available from the Monitor Analog Outputs In fact the Monitor Analog Outputs are not affected by the selection of AC or DC When changing to AC or DC previously established Relative and Alarm setpoints are maintained but Max Hold operation changes Refer to Paragraph 3 2 for details of Max Hold operation FILTER The Filter key is used to initiate the display filter function The display filter function is used to quiet the display and make it more readable when the probe is exposed to a noisy field The display filter can be turned on or off independently for each probe channel The filter does not apply directly to the Vector display but the Vector computation will use the filtered computation values and the filtering of the components can greatly enhance the stability of the Vector reading Care should be taken when using the filter on changing fields because it may level off peaks and slow the response of the instrument The filter function of the Model 460 is user configurable so that desired field changes can be seen and noise blocked The filter also acts to quiet noise within the instrument making an additional digit of usable resolution available with the filter on in DC To turn on the display filter first press the desired channel in this case press the channel Y key Then press the Filter key and observe the following display Select With A Filter Ap Off S
144. n Lake Shore Model 460 Gaussmeter User s Manual 3 4 SELECT RANGE AND AUTO RANGE Each channel of the Model 460 is capable of reading any of the Lake Shore probe types High Stability High Sensitivity or Ultra High Sensitivity The three probes permit the Model 460 to sense fields as low as 0 01 mG and as high as 300 kG The full scale ranges for each probe sensitivity along with the fixed display resolution are shown in the following tables The range for the Vector Magnitude display is not directly settable Instead Vector Magnitude will display the same resolution as the highest range setting of the component channels For example if the Vector Magnitude is set for XYZ and all three channels are in the 3 kG range the Vector Magnitude range will also be 3 kG If one of the channels is switched to 30 kG does not matter which one the Vector Magnitude range will also switch to 30 kG High Stability Probe HST Pp Gauss Testa Resolution Range AC or DC Range AC or DC i with Filter off PC Filter On with Filter off PC Filter On 300 kG 0 01 kG 0 001 kG 0 001T 0 0001 T 30 kG 0 001kG 0 0001 kG 0 0001T 0 00001 T 0 0001 kG 0 00001 kG 300 mT 0 01mT 0 001 mT 300 G 0 01 G 0 001 G 0 001mT 0 0001 mT High Sensitivity Probe HSE OOo i Gauss O OS Ultra High Sensitivity Probe UHS Po Gauss Tesla OE Resolution Resolution Range AC or DC Range AC or DC 3 with Filter off
145. n B Uo H M for SI and B H 47M for cgs where H magnetic field strength M magnetization and Uo permeability of free space 4r x 10 7 Him magnetic hysteresis The property of a magnetic material where the magnetic induction B for a given magnetic field strength H depends upon the past history of the samples magnetization magnetic induction B See magnetic flux density magnetic moment m This is the fundamental magnetic property measured with dc magnetic measurements systems such as a vibrating sample magnetometer extraction magnetometer SQUID magnetometer etc The exact technical definition relates to the torque exerted on a magnetized sample when placed in a magnetic field Note that the moment is a total attribute of a sample and alone does not necessarily supply sufficient information in understanding material properties A small highly magnetic sample can have exactly the same moment as a larger weakly magnetic sample see Magnetization Measured in SI units as A m and in cgs units as emu 1 emu 10 3 A m magnetic scalar potential The work which must be done against a magnetic field to bring a magnetic pole of unit strength from a reference point usually at infinity to the point in question Also know as magnetic potential magnetic units Units used in measuring magnetic quantities Includes ampere turn gauss gilbert line of force maxwell oersted and unit magnetic pole magnetization M This is a mat
146. nction for a channel you must first push the X Y Z or Vector Magnitude key Once selected all subsequent channel specific operations will affect that channel until another channel key is pressed The following is an example of how channel selection works If you want to turn Max Hold on for Channel X you must first press the Channel X key You will briefly see the following display Setting Channel a DH 276776 kG DC D 969527 kG DC D 95325 kG XYZ You may then press the Max Hold key You will see the following display The Max Hold function is described in detail in Paragraph 3 2 Max Hold OW RH rr kG DC 969527 kG DC H 953525 kG ad In fact you may press any number of applicable functions and they all will affect Channel X This will continue until another channel or the Vector Magnitude key is pressed or the unit is turned off in which case it will default back to Channel X After a short timeout the X channel display will return to normal with the Max Hold value being displayed on the first line as seen in the following display H 89275 kG MAK H ZC kG BC H 96952 kG DC 8 95266 kG DC Channel On Off Each channel may be independently turned on or off To do this press and hold the X Y Z or Vector Magnitude key For example if we wanted to turn Channel X on we would press and hold the Channel X key You will see the following display Select With A Chann
147. ndicate that entry of magnetic flux causes a positive reading See Figure 3 6 If the exact direction of the magnetic field is unknown the proper magnitude is determined by turning on Max Hold and slowly adjusting the probe As the probe turns and the measured field rises and falls its maximum value is held on the display Make note of the probe orientation at the maximum reading to identify the field orientation NOTE Determining field direction is not necessary when using a 3 axis probe with Vector ON The Lake Shore Logo Towards North Pole B Se h Transverse Probe Orientation For Positive Measurement A ESSN eer a i Axial Probe Orientation For Positive Measurement ol yea Bx 2 Axis Probe Sensor Orientation W ae Bx 3 Axis Probe Sensor Orientation Arrows indicate direction of positive flux vector Small letters are placed on the 2 and 3 axis probe tips to indicate that entry of magnetic flux will cause a positive reading C 460 3 6 eps Figure 3 6 Probe Orientation For Positive Measurement 3 26 Operation Lake Shore Model 460 Gaussmeter User s Manual 3 17 4 Probe Accuracy Considerations NOTE Probe readings are dependent upon the angle of the sensor in relation to the magnetic field The further from 90 the angle between the probe and the field the greater the percentage of error For example a 5 deviation causes a 0 4 error a 10 deviation causes a 1 5 error etc NOTE
148. ng accuracy of the Vector Magnitude will be affected by the individual component settings GAUSS TESLA The Model 460 displays magnetic field values in gauss G or tesla T Press Gauss Tesla to toggle the display between the two units Changing gauss tesla settings automatically applies to all X Y Z and vector magnitude readings The relation between gauss and tesla is 1 G 0 0001 T or 1 T 10 000 G When the field units are changed relative and alarm setpoints convert to the new units with no interruption in operation Corrected and Monitor Analog Outputs are not affected by a units change When tesla is selected the Model 460 front panel displays AC or DC field values followed by T for tesla mT for millitesla or uT for microtesla However to obtain complete field readings over the IEEE 488 Serial Interface the user must also send a FIELDM command to define the multiplier When gauss is selected the Model 460 front panel displays AC or DC field values followed by kG for kilogauss G for gauss or mG for milligauss However to obtain complete field readings over the IEEE 488 Serial Interface the user must also send a FIELDM command to define the multiplier Operation 3 11 3 9 3 12 Lake Shore Model 460 Gaussmeter User s Manual RELATIVE SET AND RELATIVE ON OFF The relative function lets the user see small variations in larger fields The setpoint or center of the relative reading is set with the Relative Set key There
149. ng the pins For best results secure the connector to the rear panel using the two thumbscrews A tight connector keeps the cable secure and prevents interference To use a 2 or 3 Axis probe X Y and Z probes must be connected to their respective rear panel connectors On multi axis probes each connector is marked with a channel axis designation The Y and Z probes will not function if the X channel is turned off or the X connector is removed Refer to Paragraph 3 17 for additional probe considerations When power is turned on the instrument reads parameters from probe memory The probe is ready to use No parameters need to be entered into the Model 460 However the Zero Probe function should be performed the first time a probe is used with the instrument and periodically during use Installation 2 3 2 5 1 2 6 2 7 2 4 Lake Shore Model 460 Gaussmeter User s Manual Attachment To A Hall Generator The Model MCBL XX has a 15 pin D Style connector on one end for direct attachment to any of the PROBE INPUT connections on the back panel of the Model 460 Gaussmeter Four tinned wires are provided for connection to the Hall Generator The leads may be soldered directly to these wires The cable comes in two lengths the MCBL 6 is 2 meters 6 feet and the MCBL 20 is 6 meters 20 feet Green Wire Current to Sensor Red Wire 6 Foot Cable to Gaussmeter from Sensor Yellow Wire d Blue Wire Hall Volta
150. no strict convention exists for the use of remanent induction and remanence and in some contexts the two terms may be used interchangeably remanent induction The remaining magnetic induction in a magnetic material after an applied field is reduced to zero Also see remanence repeatability The closeness of agreement among repeated measurements of the same variable under the same conditions resolution The degree to which nearly equal values of a quantity can be discriminated display resolution The resolution of an instrument s physical display This is not always the same as the measurement resolution of the instrument Decimal display resolution specified as n digits has 10 possible display values A resolution of n and one half digits has 2 x 10 possible values measurement resolution The ability of an instrument to resolve a measured quantity For digital instrumentation this is often defined by the analog to digital converter being used A n bit converter can resolve one part in 2 The smallest signal change that can be measured is the full scale input divided by 2 for any given range Resolution should not be confused with accuracy root mean square RMS The square root of the time average of the square of a quantity for a periodic quantity the average is taken over one complete cycle Also known as effective value RS 232C Bi directional computer serial interface standard defined by the Electronic Industries Association EIA The in
151. nstructions inspection and unpacking in Paragraph 2 1 repackaging for shipment in Paragraph 2 2 definition of rear panel connections in Paragraph 2 3 and initial setup and system checkout procedure in Paragraph 2 4 INSPECTION AND UNPACKING Inspect shipping containers for external damage Make all claims for damage apparent or concealed or partial loss of shipment in writing to Lake Shore within five 5 days from receipt of goods If damage or loss is apparent please notify the shipping agent immediately Open the shipping containers Use the packing list included with the system to verify receipt of the instrument probes accessories and manual Inspect for damage Inventory all components supplied before discarding any shipping materials If there is freight damage to the instrument file proper claims promptly with the carrier and insurance company and notify Lake Shore Notify Lake Shore immediately of any missing parts Lake Shore cannot be responsible for any missing parts unless notified within 60 days of shipment Refer to the standard Lake Shore Warranty on the A Page behind the title page REPACKAGING FOR SHIPMENT If it is necessary to return the Model 460 probe s or accessories for repair or replacement a Return Goods Authorization RGA number must be obtained from a factory representative before returning the instrument to our service department When returning an instrument for service the following information must
152. nstructions in the User s Manual are followed there should be no degradation in EMC performance Pay special attention to instrument cabling Improperly installed cabling may defeat even the best EMC protection For the best performance from any precision instrument follow the grounding and shielding instructions in the User s Manual In addition the installer of the Model 460 should consider the following e Leave no unused or unterminated cables attached to the instrument e Make cable runs as short and direct as possible e Do not tightly bundle cables that carry different types of signals e Add the clamp on ferrite filter Part Number 109 053 included with the connector kit to the serial interface cable near the instrument rear panel when that interface is used Lake Shore Model 460 Gaussmeter User s Manual TABLE OF CONTENTS Chapter Paragraph Title Page 1 INTRODUCTION E 1 1 1 0 General vet he ee Ee Ae ele Es 1 1 1 1 Product Description s 4 68 fies Ee hes Sao SHLAA a 1 1 1 2 eeler Le 1 4 1 3 SAIS LY TOIAN E eeh eet seater T Deets Det 1 5 1 4 Salely ne EE EEN 1 5 SZ INSTALLATION eegene eeler ege 2 1 2 0 Generalsucsiith ei ee ae Ee eee ee e aA a a e E a E Eo 2 1 2 1 Inspection and Unpacking ci steitve dee eeececen bath cveencehceksclvn lease steed aarian EEA REE aeaa Kaa TEn E AKEN 2 1 2 2 Repackaging For Shipment asrine eree i ea EEN ENEE Ode N 2 1 2 3 Rea i Panel Detmton ji a a et a Eed aa a ae a aa A E aaa E an eaa
153. nt CAUTION Always turn off the instrument before making any rear panel connections This is especially critical when making probe to instrument connections WARNING CHANNEL X CHANNEL Y CHANNEL Z ANALOG OUT ANAL E OUT 2 E OUT PROBE INPUT f ANALOG OUT PROBE INPUT IEEE 488 INTERFACE N ronen vomi SERIAL VO A em SPE E om DOr mp m L vm ammo 460_Back bmp Description Pin Definition Line Input Assembly Paragraph 2 4 Figure 2 2 IEEE 488 INTERFACE Connector Paragraph 6 5 1 Figure 6 5 SERIAL I O RJ 11 Connector Paragraph 4 2 1 Figure 6 4 ANALOG OUT Corrected BNC Paragraph 2 6 and 3 13 1 Figure 6 3 ANALOG OUT Monitor BNC Quantity 3 Paragraph 2 6 and 3 13 2 Figure 6 3 PROBE INPUT 15 pin D Style Connector Quantity 3 Paragraph 2 5 Figure 6 2 Figure 2 1 Model 460 Rear Panel 2 2 Installation 2 4 2 4 1 2 4 2 2 4 3 2 5 Lake Shore Model 460 Gaussmeter User s Manual LINE INPUT ASSEMBLY This section covers line voltage and fuse verification in Paragraph 2 4 1 power cord in Paragraph 2 4 2 and power switch in Paragraph 2 4 3 Line Voltage and Fuse Verification To verify proper line voltage selection look at the indicator in the window on the fuse drawer of the line input assembly Line voltage should be in the range shown in the specifications listed on the back of the instrument See Figure 2 2 If not chan
154. nt when the Model 460 completes its message transfer on output They also identify the end of an input message This command works only with the IEEE 488 Interface and does not change the serial terminators Refer to Paragraph 3 11 Terminator Query TERM term lt terminator gt term n Refer to command for description Remote Operation 4 29 Lake Shore Model 460 Gaussmeter User s Manual 4 3 3 Device Specific Commands ACDC Input Format Remarks ACDC Input Returned Format ALARM Input Format ALARM Input Returned Format ALLF Input Returned Format Remarks ALMB Input Format ALMB Input Returned Format 4 30 AC DC Magnetic Field Reading Command ACDC lt mode gt term n lt mode gt 0 DC 1 AC Configures the unit for AC or DC measurements The AC field is further defined by the PRMS Peak or RMS command Refer to Paragraph 3 5 AC DC Magnetic Field Reading Query ACDC term lt mode gt term n Refer to command for description Alarm Function On Off Command ALARM lt state gt term n lt state gt 0 Off 1 On Refer to Paragraph 3 10 Alarm Query ALARM term lt state gt term n Refer to command for description All Fields Query ALLF term lt field value gt term nnn nn lt field value gt Returns sign 4 or 5 digits and places decimal point appropriate to range Returns the X axis reading the Y axis the Z axis
155. nterface Program Type exit to end program Command Response 15 Type in a command or query in the Command box as described in Paragraph 4 2 7 3 16 Press Enter or select the Send button with the mouse to send command 17 Type Exit and press Enter to quit Remote Operation Lake Shore Model 460 Gaussmeter User s Manual Table 4 6 Visual Basic Serial Interface Program Public gSend As Boolean Global used for Send button state Private Sub cmdSend_ Click gSend True End Sub Routine to handle Send button press Set Flag to True Private Sub Form Load Dim strReturn As String Dim strHold As String Dim Term As String Dim ZeroCount As Integer Dim strCommand As String frmSerial Show Term Chr 13 amp Chr 10 ZeroCount 0 strReturn strHold mn If frmSerial MSComml1 PortOpen True Then frmSerial MSComm1 PortOpen False End If frmSerial MSComm1 CommPort 1 frmSerial MSComml1 Settings 9600 0 7 1 frmSerial MSComml1 InputLen 1 frmSerial MSComml1 PortOpen True Do Do DoEvents Loop Until gSend True gSend False strCommand frmSerial txtCommand Text strReturn strCommand UCase strCommand If strCommand EXIT Then End End If frmSerial MSComml1 Output strCommand amp Term If InStr strCommand lt gt 0 Then While ZeroCount lt 20 And strHold lt gt Chr 10 If frmSerial MSComm1 InBufferCount 0 Then frmSerial Timer
156. ntinued MODE Input Format Remarks Example MODE Input Returned Format SLEEP Input Format Remarks SLEEP Input Returned Format TERM Input Format Remarks TERM Input Returned Format Local Remote Mode Command MODE lt mode gt term n lt mode gt 0 Local Mode 1 Remote Mode 2 Remote Mode with Local Lockout Press the front panel Local key to set the Model 460 to local provided the key has not been disabled by local lockout The Model 460 powers up in local mode Refer to Paragraph 3 11 At the end of a command string MODE 0 maintains constant local operation Local Remote Mode Query MODE term lt mode gt term n Refer to command for description Current Source Command SLEEP lt state gt term n lt state gt 0 On 1 Off Turns off all current sources Useful to gather a sensitive measurement elsewhere in a system where gaussmeter current sources may interfere with measurement Refer to Paragraph 3 16 2 Current Source Query SLEEP term lt state gt term n Refer to command for description Terminator Command TERM lt terminator gt term n lt terminator gt 0 Carriage return and line feed CR LFE 1 Line feed and carriage return LF CR 2 Line feed LFE 3 No terminating characters EOI line set with last data byte if enabled End Sets the terminating character type Terminating characters are se
157. nual ranging may be better in some conditions Pressing the Auto Range key shows the following display Select With at Auto Range 0n Off Setting Channel a Pressing the Auto Range or A or W keys cycles between On and Off Push the Enter key to accept the new setting or the Escape key to leave the setting as is and return to the normal display Auto Ranging should not be used with Peak and Max Hold operation Also Auto Ranging should not be used when measuring small fields in a large background field i e measuring a small DC field in presence of a large AC field or measuring a small AC field in the presence of a large DC field AC DC AND PEAK RMS After pressing the channel key pressing the AC DC key toggles between AC and DC measurements for that channel The annunciator immediately changes from DC to PK or RMS as applicable However one update cycle is required for a new display value The Model 460 updates the field reading several times per second Please note that for the Vector Magnitude display to be logical each of the component channels must have the same AC RMS Peak settings If they are not the Vector display will show Component Mismatch However even when the Component Mismatch message is being displayed the X Y and Z channel readings are still individually correct In DC operation the display shows the DC field at the probe with sign orientation followed by the appropriate f
158. odel 4065 Large Zero Gauss Chamber 5 13 Model 4001 RJ 11 Cable Assembly AAA 5 14 Model 4002 RJ 11 to DB 25 Adapter AAA 5 14 Model 4003 RJ 11 to DE 9 Adapter AAA 5 14 Power D a CE O EAEE E AE E AE deeg 6 3 PROBE INPUT Connector Details isis enire a a aee a a i e E e aao 6 4 ANALOG OUT Corrected and Monitor BNC Connector Details 00 0 0 ecceeseeeeeeeeeeeeeneeeeeeeeeeeeeeeeeeeneeeneeeeeaes 6 4 SERIAL O Connector RUE 6 4 IEEE 488 Rear Panel Connector Details 6 5 Model 4001 RJ 11 Cable Assembly Wiring Details 6 6 Model 4002 Ru 11 to DB 25 Adapter Wiring Details AA 6 6 Model 4003 Ru 11 to DE 9 Adapter Wiring Details AAA 6 6 Location Of Operating Software EPROM sssseesessissssssresrresinstitsttnttttttttttnsttnstrattuntinatanntnnttnntenatnnetnnenneen 6 7 Hall Generator TEO vaca sve nee deeg dacteeel dee Seg tenet na dead ea aaa C 2 Axial and Transverse Confiourations AE nAtEnstnatnntEnntEnEE nenne ennen C 2 Typical Hall Generator HOOKUP 28 seeeegersgEeeggedE LA Shee czas avec ciate nz aaea a a a re ea E aae a swine ageatieadoes C 4 Hall Generator Input Impecdance AAA C 4 Axial Hall Generator HGA 3010 HGA 3030 amp HGCA 3010 Dimenslons ssssessessssersrernrnenenenrnrnnnnnnnrnnns C 5 Transverse Hall Generator HGT 3010 HGT 3030 amp HGCT 3020 Dimensions cccceeeeeeeeeeeeeeeeeeeeees C 5 Transverse Hall Generator HGT 1010 Dimensions c cceeceeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeaeeeseeeseeeseeeeieeesieeenaes C 6
159. or severed cables should be returned to Lake Shore for repair please understand that probes are not always repairable When probes are installed on the gaussmeter but not in use the protective tubes provided with many probes should be placed over the probe handle and stem in order to protect the tip When the gaussmeter is not in use the probes should be stored separately in some type of rigid container The cardboard and foam container that Lake Shore probes are shipped in may be retained for probe storage For further details on available accessories and probes refer to Chapter 5 Do not bend from tip of probe e fo TT Lakeshore The tip is Flexible Transverse Probe VERY FRAGILE Maximum Bend Angle C 460 3 5 eps Figure 3 5 Maximum Flexible Probe Bend Radius Operation 3 25 Lake Shore Model 460 Gaussmeter User s Manual 3 17 3 Probe Polarity In the DC mode of operation the orientation of the probe affects the polarity reading of the gaussmeter On a transverse probe the Lake Shore name printed on the handle indicates the side for positive flux entry On an axial probe positive flux entry is always from the front of the probe On 2 axis probes the positive flux entry for Bx is on the flat side of the probe tip and By is from the front of the probe On 3 axis probes the positive flux entry for Bx and By are on the flat sides of the probe tip and Bz is from the front of the probe Small labels on the probe tip i
160. orange and automatic probe zero With a factory calibrated linearization table the instrument can compensate for inherent nonlinearity in the sensor and calculate the field more accurately than a single point sensitivity would allow If the probe is equipped with a temperature sensor the Model 460 reads temperature along with the field signal and makes continuous adjustments to the calculated field value Vector magnitude calculations can be done by the instrument when using two and three axis probes 460 3 Channel Gaussmeter wm w EC be i DEED 460_Front bmp Figure 1 1 Model 460 Front Panel Introduction 1 1 Lake Shore Model 460 Gaussmeter User s Manual Product Description Continued Measurement Modes The Model 460 has three operating modes DC RMS and Peak The instrument is well suited for DC measurements because accuracy and resolution are best in DC mode Noise floor is so low that 5 digit measurements are possible Low noise and high stability are ideal for multiple axis field mapping applications Changing fields which are often used in material analysis systems can be measured on all three inputs up to 18 times a second over a computer interface with full resolution In RMS mode the Model 460 can measure periodic AC fields from 10 to 400 Hertz True RMS conversion is done by instrument circuitry that accommodates wave forms with crest factors up to 7 RMS mode is best suited for meas
161. ounds per square inch psi A unit of pressure 1 psi 6 89473 kPa Variations include psi absolute psia measured relative to vacuum zero pressure where one atmosphere pressure equals 14 696 psia and psi gauge psig where gauge measured relative to atmospheric or some other reference pressure A 4 Glossary of Terminology Lake Shore Model 460 Gaussmeter User s Manual ppm Parts per million e g 4 x 10 6 is four parts per million precision Careful measurement under controlled conditions which can be repeated with similar results See repeatability Also means that small differences can be detected and measured with confidence See resolution prefixes SI prefixes used throughout this manual are as follows Factor Prefix Symbol Factor Prefix Symbol 1024 yotta Y 107 deci d 10 zetta Z 10 centi c 1018 exa E 10 milli m 1018 peta P 10 micro u 101 tera T 10 nano n 10 giga G 10 2 pico p 10 mega M 10 15 femto f 10 kilo k 10 18 atto a 102 hecto h due zepto Z 10 deka da 10724 yocto y probe A long thin body containing a sensing element which can be inserted into a system in order to make measurements Typically the measurement is localized to the region near the tip of the probe remanence The remaining magnetic induction in a magnetic material when the material is first saturated and then the applied field is reduced to zero The remanence would be the upper limit to values for the remanent induction Note that
162. p LPT Interface m Termination Methods Timeouts Si a i GPIBO zl M SendEOlatendof write 72 10sec D GPIB Address M Terminate Read on EOS ar Primary M Set EO with EOS on Write h z on aer D Properties Refresh R I 8 bit EOS Compare Secondary NONE 7 fio EOS Byte MV Readdress Figure 4 2 DEV 12 Device Template Configuration 4 6 Remote Operation Lake Shore Model 460 Gaussmeter User s Manual 4 1 4 2 Visual Basic IEEE 488 Interface Program Setup This IEEE 488 interface program works with Visual Basic 6 0 VB6 on an IBM PC or compatible with a Pentium class processor A Pentium 90 or higher is recommended running Windows 95 or better It assumes your IEEE 488 GPIB card is installed and operating correctly refer to Paragraph 4 1 4 1 Use the following procedure to develop the IEEE 488 Interface Program in Visual Basic Start VB6 Choose Standard EXE and select Open Resize form window to desired size On the Project Menu select Add Module select the Existing tab then navigate to the location on your computer to add the following files Niglobal bas and Vbib 32 bas 5 Add controls to form a Add three Label controls to the form b Add two TextBox controls to the form c Add one CommandBuiton control to the form 6 On the View Menu select Properties Window 7 Inthe Properties window use the dropdown list to select between the different controls of the curren
163. pe of this limited warranty Some countries states or provinces do not allow limitations on an implied warranty so the above limitation or exclusion might not apply to you This warranty gives you specific legal rights and you might also have other rights that vary from country to country state to state or province to province Further with regard to the United Nations Convention for International Sale of Goods CISC if CISG is found to apply in relation to this agreement which is specifically disclaimed by Lake Shore then this limited warranty excludes warranties that a the Product is fit for the purpose for which goods of the same description would ordinarily be used b the Product is fit for any particular purpose expressly or impliedly made known to Lake Shore at the time of the conclusion of the contract c the Product is contained or packaged in a manner usual for such goods or in a manner adequate to preserve and protect such goods where it is shipped by someone other than a carrier hired by Lake Shore Lake Shore disclaims any warranties of technological value or of non infringement with respect to the Product and Lake Shore shall have no duty to defend indemnify or hold harmless you from and against any or all damages or costs incurred by you arising from the infringement of patents or trademarks or violation or copyrights by the Product THIS WARRANTY IS NOT TRANSFERRABLE This warranty is not transferrable Except to the exten
164. provides information on the accessories and probes available for the Model 460 Gaussmeter Model numbers are detailed in Paragraph 5 1 accessories in Paragraph 5 2 Lake Shore standard probes in Paragraph 5 3 Helmholtz coils in Paragraph 5 4 and reference magnets in Paragraph 5 5 5 1 MODELS The list of Model 460 Model numbers is provided as follows Model Description 460 Standard Model 460 3 Channel Gaussmeter Features 3 volt corrected analog output 460 10 Optional Model 460 3 Channel Gaussmeter Features 10 volt corrected analog output Power configurations the instrument is configured at the factory for customer selected power as follows 100V US NEMA 5 15 120V US NEMA 5 15 220V EU CEE 7 7 240V EU CEE 7 7 240V UK BS 1363 240V Swiss SEV 1011 220V China GB 1002 zl 1 OO Oo AJOJN ch 5 2 ACCESSORIES Accessories are devices that perform a secondary duty as an aid or refinement to the primary unit 109 053 Clamp On Ferrite Filter Electromagnetic Compatibility EMC noise suppression device 115 006 Detachable 120 VAC Line Cord RJ 11 Cable Assembly Four Wire Cable Assembly with RJ 11 plugs on each end Used with RS 232C Interface Cable is 4 meters 14 feet long See Figure 5 17 RJ 11 to DB 25 Adapter Adapts RJ 11 receptacle to female DB 25 connector Connects Model 460 to RS 232C Serial Port on rear of Customer s computer See Figure 5
165. ro if the instrument loses power or is turned off The setting cannot be changed from the front panel Refer to Paragraph 3 13 3 The command AOCON 50 25 sets output to 50 25 of full scale This is 5 025 volts for a 10 volt output or 1 5075 volts for a 3 volt output Analog Output Control Mode Query AOCON term lt percent gt term tnnn nn Refer to command for description Auto Range Command AUTO lt state gt term n lt state gt 0 Auto Range Off 1 Auto Range On Refer to Paragraph 3 4 Auto Range Query AUTO term lt state gt term n Refer to command for description Channel Command CHNL lt channel gt term a lt channel gt X Channel X Y Channel Y Z Channel Z V Vector Magnitude Channel Directs commands to the specified channel Subsequent commands apply to the specified channel until a new CHNL command is sent or the unit is powered off and back on again Refer to Paragraph 3 1 4 Channel Query CHNL term lt channel gt term a Refer to command for description Remote Operation Lake Shore Model 460 Gaussmeter User s Manual Device Specific Commands Continued FIELD Input Returned Format Remarks FIELDM Input Returned Format Remarks FILT Input Format Remarks FILT Input Returned Format FNUM Input Format Remarks FNUM Input Returned Format Remote Operation Magnetic Field R
166. rties of the controls as defined in Table 4 5 11 Save the program Remote Operation 4 17 Lake Shore Model 460 Gaussmeter User s Manual Table 4 5 Serial Interface Program Control Properties Current Name Property New Value Label Name IbIExitProgram Caption Type exit to end program Label2 Name lbICommand Caption Command Label3 Name lbIResponse Caption Response Texti Name txtCommand Text lt blank gt Text2 Name txtResponse Text lt blank gt Command1 Name cmdSend Caption Send Default True Form1 Name frmSerial Caption Serial Interface Program Timeri Enabled False Interval 10 12 Add code provided in Table 4 6 a Inthe Code Editor window under the Object dropdown list select General Add the statement Public gSend as Boolean b Double Click on cmdSend Add code segment under Private Sub cmdSend_Click as shown in Table 4 6 c Inthe Code Editor window under the Object dropdown list select Form Make sure the Procedure dropdown list is set at Load The Code window should have written the segment of code Private Sub Form_Load Add the code to this subroutine as shown in Table 4 6 d Double Click on the Timer control Add code segment under Private Sub Timer1_Timer as shown in Table 4 6 e Make adjustments to code if different Com port settings are being used 13 Save the program 14 Run the program The program should resemble the following ig Serial I
167. s perpendicular to the plane of the sensor This is the condition that exists during factory calibration The greater the deviation from orthogonality from right angles in either of three axes the larger the error of the reading For example a 5 variance on any one axis causes a 0 4 error a 10 misalignment induces a 1 5 error etc See Figure 3 7 Tolerance of instrument probe and magnet must be considered for making critical measurements The accuracy of the gaussmeter reading is better than 0 20 of reading and 0 05 of range Absolute accuracy readings for gaussmeters and Hall probes is a difficult specification to give because all the variables of the measurement are difficult to reproduce For example a 1 error in alignment to the magnetic field causes a 0 015 reading error Finally the best probes have an accuracy of 0 15 This implies that the absolute accuracy measurement of a magnetic field is not going to reliably be better than 0 15 under the best of circumstances and more likely to be 0 20 to 0 25 29 3 B 13 4 45 6 0 3 4 20 w 15 1 5 10 0 4 5 0 0 Error Deviation from perpendicular a Effect of angular variations on percentage of reading error where percent error 1 cos a 100 C 460 3 7 eps Figure 3 7 Effect Of Angle On Measurements Operation 3 27 Lake Shore Model 460 Gaussmeter User s Manual This Page Intentionally Left Blank 3 28 Operation Lake Shore Mod
168. ser s Manual gilbert Gb A cgs electromagnetic unit of the magnetomotive force required to produce one maxwell of magnetic flux in a magnetic circuit of unit reluctance One gilbert is equal to 10 4 ampere turn Named for William Gilbert 1540 1603 an English physicist who hypothesized that the Earth is a magnet gilbert per centimeter Practical cgs unit of magnet intensity Gilberts per cm are the same as oersteds Greek alphabet The Greek alphabet is defined as follows Alpha a A lota H I Rho p P Beta B B Kappa K K Sigma o Gamma Y T Lambda A Tau T T Delta 8 A Mu u M Upsilon v Y Epsilon E Nu v N Phi o 0 Zeta G Z Xi E Chi H X Eta n H Omicron o O Psi y KN Theta 0 O Pi n TI Omega m Q ground A conducting connection whether intentional or accidental by which an electric circuit or equipment is connected to the earth or to some conducting body of large extent that serves in place of the earth Note It is used for establishing and maintaining the potential of the earth or of the conducting body or approximately that potential on conductors connected to it and for conducting ground current to and from the earth or of the conducting body H Symbol for magnetic field strength See Magnetic Field Strength Hall effect The generation of an electric potential perpendicular to both an electric current flowing along a thin conducting material and an external magnetic field applied at right angles to the current Named for Ed
169. ss forms the Listen Address LA Adding 64 to the primary address forms the Talk Address TA EXAMPLE Selecting a primary address of 10 yields the following 10 32 42 10 64 74 Listen address Talk address IBCONF EXE eps Figure 4 3 Typical National Instruments GPIB Configuration from IBCONF EXE Remote Operation 4 11 4 12 Lake Shore Model 460 Gaussmeter User s Manual Table 4 3 Quick Basic IEEE 488 Interface Program IEEEEXAM BAS EXAMPLE PROGRAM FOR IEEE 488 INTERFACE This program works with QuickBasic 4 0 4 5 on an IBM PC or compatible The example requires a properly configured National Instruments GPIB PC2 card The REM SINCLUDE statement is necessary along with a correct path to the file QBDECL BAS CONFIG SYS must call GPIB COM created by IBCONF EXE prior to running Basic There must be QBIB QBL library in the QuickBasic Directory and QuickBasic must start with a link to it All instrument settings are assumed to be defaults Address 12 Terminators lt CR gt lt LF gt and EOI active To use type an instrument command or query at the prompt The computer transmits to the instrument and displays any response If no query is sent the instrument responds to the last query received Type EXIT to exit the program REM SINCLUDE c gpib pc qbasic qbdecl bas CLS PRINT IEEE 488 COMMUNICATION PROGRAM PRINT CALL IBFIND dev12 DEV12 TERMS CHR 13 CHR 10 IN SPACE 20
170. stomers not to turn the field and temperature compensation off The reading accuracy can be substantially reduced with the Field Compensation turned off Field and Temperature Compensation may be disabled by the user by selecting channel then pressing and holding the Filter key for 5 seconds After pressing and holding the Filter key for 5 seconds the following Field Compensation display will appear Select With at Field Come Ap Off Setting Channel Z To improve accuracy many probes have a magnetic field compensation table stored in a PROM Selecting Field Compensation Off will cause the Model 460 to ignore this table Pressing the A or V keys cycles between On and Off Push the Enter key to accept the new setting or the Escape key to leave the setting as is and return to the normal display If the probe does not have field compensation the setting is ignored Select With at Teme Come 4 0n OFF Setting Channel Z Some probes also feature temperature compensation Selecting Temperature Compensation Off will cause the Model 460 to ignore this data Pressing the A or W keys cycles between On and Off Push the Enter key to accept the new setting or the Escape key to leave the setting as is and return to the normal display If the probe does not have temperature compensation the setting is ignored Although the field and temperature compensation functions are not applicable to the Vector Magnitude display the readi
171. structure in which the field is produced in an air gap between pole faces The coil can be water cooled copper or aluminum or superconductive electron An elementary particle containing the smallest negative electric charge Note The mass of the electron is approximately equal to 1 1837 of the mass of the hydrogen atom electrostatic discharge ESD A transfer of electrostatic charge between bodies at different electrostatic potentials caused by direct contact or induced by an electrostatic field error Any discrepancy between a computed observed or measured quantity and the true specified or theoretically correct value or condition Fahrenheit F Scale A temperature scale that registers the freezing point of water as 32 F and the boiling point as 212 F under normal atmospheric pressure See Temperature for conversions flux The electric or magnetic lines of force in a region gamma A cgs unit of low level flux density where 100 000 gamma equals one gauss or 1 gamma equals 10 5 gauss gauss G The cgs unit for magnetic flux density B 1 gauss 10 tesla 1 Mx cm line cm Named for Karl Fredrich Gauss 1777 1855 a German mathematician astronomer and physicist gaussian system units A system in which centimeter gram second units are used for electric and magnetic qualities general purpose interface bus GPIB Another term for the IEEE 488 bus A 2 Glossary of Terminology Lake Shore Model 460 Gaussmeter U
172. strument to remove dust grease and other contaminants 1 Clean front and back panels and case with soft cloth dampened with a mild detergent and water solution NOTE Do not use aromatic hydrocarbons or chlorinated solvents to clean the instrument They may react with the plastic materials used in the case or the silk screen printing on the back panel 2 Clean the surface of printed circuit boards PCBs with clean dry air at low pressure ELECTROSTATIC DISCHARGE Electrostatic Discharge ESD may damage electronic parts assemblies and equipment ESD is a transfer of electrostatic charge between bodies at different electrostatic potentials caused by direct contact or induced by an electrostatic field The low energy source that most commonly destroys Electrostatic Discharge Sensitive ESDS devices is the human body which generates and retains static electricity Simply walking across a carpet in low humidity may generate up to 35 000 volts of static electricity Current technology trends toward greater complexity increased packaging density and thinner dielectrics between active elements which results in electronic devices with even more ESD sensitivity Some electronic parts are more ESDS than others ESD levels of only a few hundred volts may damage electronic components such as semiconductors thick and thin film resistors and piezoelectric crystals during testing handling repair or assembly Discharge voltages below 4000 volts c
173. t bit weighting gt nnn term Acts like a serial poll but does not reset the register to all zeros The integer returned represents the sum of the bit weighting of the status flag bits that are set in the Status Byte Register Refer to Paragraph 4 1 3 1 for a list of status flags Remote Operation 4 25 Lake Shore Model 460 Gaussmeter User s Manual Common Commands Continued TST Input Returned Format Remarks WAI Input Remarks 4 26 Self Test Query TST term lt status gt n lt status gt 0 no errors found 1 errors found The Model 460 reports status based on test done at power up Wait to Continue Command WAI term Send WAI as the last command in a command string followed by appropriate termination It cannot be embedded between other commands Remote Operation Lake Shore Model 460 Gaussmeter User s Manual 4 3 2 Interface Commands ADDR Input Format Remarks ADDR Input Returned Format BAUD Input Format BAUD Input Returned Format BRIGT Input Format BRIGT Input Returned Format CODE Input Format CODE Input Returned Format IEEE Address Command ADDR lt address gt term nn lt address gt An integer from 1 to 30 Address 0 and 31 are reserved The Model 460 is factory preset to Address 12 Refer to Paragraph 3 11 IEEE Address Query ADDR term lt address gt term nn Refer to command for descr
174. t ibility conduct ance susceptibility x Parameter giving an indication of the response of a material to an applied magnetic field The susceptibility is the ratio of the magnetization M to the applied field H y M H In both SI units and cgs units the volume susceptibility is a dimensionless parameter Multiply the cgs susceptibility by 4x to yield the SI susceptibility See also Initial Susceptibility and Differential Susceptibility As in the case of magnetization the susceptibility is often seen expressed as a mass susceptibility or a molar susceptibility depending upon how M is expressed Glossary of Terminology A 5 Lake Shore Model 460 Gaussmeter User s Manual temperature scales See Kelvin Scale Celsius Scale and ITS 90 Proper metric usage requires that only kelvin and degrees Celsius be used However since degrees Fahrenheit is in such common use all three scales are delineated as follows Boiling point of wate 373 15 K 100 C 212 F Triple point of wate 273 16 K Freezing point of water 273 15 K 0 C 32 F Absolute zero OK 273 15 C 459 67 F kelvin Celsius Fahrenheit To convert kelvin to Celsius subtract 273 15 To convert Celsius to Fahrenheit multiply C by 1 8 then add 32 or F 1 8 x C 32 To convert Fahrenheit to Celsius subtract 32 from F then divide by 1 8 or C F 32 1 8 temperature coefficient measurement The measurement accuracy of an instrument is affected by changes in
175. t prohibited by applicable law neither Lake Shore nor any of its subsidiaries affiliates or suppliers will be held liable for direct special incidental consequential or other damages including lost profit lost data or downtime costs arising out of the use inability to use or result of use of the product whether based in warranty contract tort or other legal theory regardless whether or not Lake Shore has been advised of the possibility of such damages Purchaser s use of the Product is entirely at Purchaser s risk Some countries states and provinces do not allow the exclusion of liability for incidental or consequential damages so the above limitation may not apply to you This limited warranty gives you specific legal rights and you may also have other rights that vary within or between jurisdictions where the product is purchased and or used Some jurisdictions do not allow limitation in certain warranties and so the above limitations or exclusions of some warranties stated above may not apply to you Except to the extent allowed by applicable law the terms of this limited warranty statement do not exclude restrict or modify the mandatory statutory rights applicable to the sale of the product to you CERTIFICATION Lake Shore certifies that this product has been inspected and tested in accordance with its published specifications and that this product met its published specifications at the time of shipment The accuracy and calibrat
176. t project Pel IEEE Interface Program of ES 10 Set the properties of the controls as defined in Table 4 1 11 Save the program Remote Operation 4 7 Lake Shore Model 460 Gaussmeter User s Manual Table 4 1 IEEE 488 Interface Program Control Properties Current Name Property New Value Label Name IbIExitProgram Caption Type exit to end program Label2 Name lbICommand Caption Command Label3 Name lbIResponse Caption Response Texti Name txtCommand Text lt blank gt Text2 Name txtResponse Text lt blank gt Command1 Name cmdSend Caption Send Default True Form1 Name frmlEEE Caption IEEE Interface Program 12 Add code provided in Table 4 2 a Inthe Code Editor window under the Object dropdown list select General Add the statement Public gSend as Boolean b Double Click on cmdSend Add code segment under Private Sub cmdSend_Click as shown in Table 4 2 c Inthe Code Editor window under the Object dropdown list select Form Make sure the Procedure dropdown list is set at Load The Code window should have written the segment of code Private Sub Form_Load Add the code to this subroutine as shown in Table 4 2 13 Save the program 14 Run the program The program should resemble the following ig IEEE Interface Program Biel E Type exit to end program Command Response 15 Type in a command or query in the Command box as described in
177. t these programs not included with the instrument the concepts illustrated apply to almost any application where these tools are available IEEE 488 Interface Board Installation for Visual Basic Program This procedure works for Plug and Play GPIB Hardware and Software for Windows 98 95 This example uses the AT GPIB TNT GPIB card 1 Install the GPIB Plug and Play Software and Hardware using National Instruments instructions 2 Verify that the following files have been installed to the Windows System folder a gpib 32 dll b gpib dll CG gpib32ft dll Files b and c will support 16 bit Windows GPIB applications if any are being used 3 Locate the following files and make note of their location These files will be used during the development process of a Visual Basic program a Niglobal bas D Vbib 32 bas NOTE If the files in Steps 2 and 3 are not installed on your computer they may be copied from your National Instruments setup disks or they may be downloaded from www ni com 4 Configure the GPIB by selecting the System icon in the Windows 98 95 Control Panel located under Settings on the Start Menu Configure the GPIB Settings as shown in Figure 4 1 Configure the DEV12 Device Template as shown in Figure 4 2 Be sure to check the Readdress box Remote Operation 4 5 Lake Shore Model 460 Gaussmeter User s Manual System Properties 2 x General Device Manager Hardware Profiles Perform RMRSALARlSE LA KE General G
178. tached remove 19 inch rack mounting brackets Use Phillips screwdriver to remove two flat head screws from center rear top and bottom of enclosure Use 5 64 hex key to remove four screws attaching top panel to unit Use 5 64 hex key to loosen two rear bottom panel screws that secure the back plastic bezel Carefully remove back plastic bezel by sliding it straight back away from the unit Slide top panel back and remove from unit Locate software EPROM U95 on main circuit board Note its orientation circular notch on front of IC See Figure 6 9 9 Use IC puller to remove existing EPROM from socket 10 Use IC insertion tool to place new EPROM into socket noting its orientation 11 Replace top of enclosure 12 Replace back bezel and use 5 64 hex key to tighten two rear bottom panel screws to secure the bezel 13 Use 5 64 hex key secure top of enclosure with four screws 14 Use Phillips screwdriver to replace two flat head screws to center rear top and bottom of enclosure 15 Reconnect power cord to rear of unit and set power switch to On 16 Perform the initial setup and system checkout refer to Paragraph 2 7 w SS On OT vs Front Operating Software EPROM Corrected Analog Output 3 Y or 10 Y Jumper Teil Jamey Rear C 460 6 9 eps Figure 6 9 Location Of Operating Software EPROM Service 6 7 6 8 6 8 Lake Shore Model 460 Gaussmeter User s Manual ERROR MESSAGES The following is a list of Mo
179. terface is single ended and non addressable scalar A quantity which has magnitude only and no direction in contrast to a vector semiconducting material A conducting medium in which the conduction is by electrons and holes and whose temperature coefficient of resistivity is negative over some temperature range below the melting point 2 semiconductor An electronic conductor with resistivity in the range between metals and insulators in which the electric charge carrier concentration increases with increasing temperature over some temperature range Note Certain semiconductors possess two types of carriers namely negative electrons and positive holes 2 sensitivity The ratio of the response or change induced in the output to a stimulus or change in the input Temperature sensitivity of a resistance temperature detector is expressed as S dR dT setpoint The value selected to be maintained by an automatic controller serial interface A computer interface where information is transferred one bit at a time rather than one byte character at a time as in a parallel interface RS 232C is a common serial interface SI Syst me International d Unit s See International System of Units stability The ability of an instrument or sensor to maintain a constant output given a constant input susceptance In electrical terms susceptance is defined as the reciprocal of reactance and the imaginary part of the complex representation of admittance suscep
180. termine units multiplier Remarks as appropriate Key x Begins common interface command Required to identify queries aa String of alpha numeric characters nn String of number characters term Terminator characters lt gt Indicated a parameter field many are command specific lt state gt Parameter field with only On Off or Enable Disable states lt field value gt Field values have the range and resolution of displayed field readings Field queries must be used with associated multiplier and units queries to obtain a complete field reading Spaces will be returned in place of unused digits lt multiplier gt u micro 10 m milli 10 blank unity k kilo 10 Remote Operation Lake Shore Model 460 Gaussmeter User s Manual Table 4 8 Command Summary Command Function Command Function Common Commands ANOD Default Analog Out Cmd CLS Clear Interface Cmd ANOD Default Analog Out Query ESE Sid Event Status Cmd ANOH Analog Out High Setpoint Cmd KESE Std Event Status Query ANOH Analog Out High Setpoint Query ESR Sid Event Register Query ANOHM Analog Out High Setpoint Multiplier IDN Identification Query ANOL Analog Out Low Setpoint Cmd OPC Operation Complete Cmd ANOL Analog Out Low Setpoint Query OPC Operation Complete Query ANOLM Analog Out Low Setpoint Multiplier RST Reset Instrument Cmd ANOS Corrected Analog Output Cmd SRE Service Request Enable Cmd ANOS Corrected Analog
181. the Vector Magnitude Press and hold to set the vector source Refer to Paragraphs 3 1 3 and 3 1 4 Vector Magnitude Max Reset Works with the Max Hold function Clears Max reading back to normal field reading Refer to Paragraph 3 2 Max Hold Turns Max Hold feature on or off Max Hold captures and displays the highest field reading Use Max Reset key to clear reading Refer to Paragraph 3 2 m a a E a oe ow B ees eem 460 3 Channel Gaussmeter Eo E pe x 460_Front bmp Figure 3 1 Model 460 Front Panel 3 1 Operation Lake Shore Model 460 Gaussmeter User s Manual Front Panel Keypad Definitions Continued 3 2 Zero Probe Select Range Auto Range AC DC Peak RMS Filter Gauss Tesla Relative Set Relative On Off Alarm Set Alarm On Off Local Interface Display Analog Out Used to zero or null effects of ambient low level fields from the probe This function is not available for Vector Magnitude Refer to Paragraph 3 3 Push to manually select the field measurement range Available ranges are dependent on which probe is installed This function is not available for Vector Magnitude Refer to Paragraph 3 4 Turns the Auto Range feature on and off Allows the Model 460 to automatically select the field measurement range This function is not available for Vector Magnitude Refer to Paragraph 3 4 Selects periodic AC or static DC magnetic fields The
182. this case we chose Channel X Press the Enter key The Corrected Analog Output is now set for 3V 3 kG The user also has the option to change the scaling of the Corrected Analog Output User defined scaling can improve resolution over a selected area of interest This can best be explained by a couple of examples The first example is a symmetrical scaling similar to the default scale i 0kG GE 1 5 KG 1 kG 0 5 kG 0 5 KG 1 KG 1 5 kG Output ER 2V 1V 1V 2V 3V Voltage T E an To enter this scale press the Analog Out Key Press the Analog Out A or V key to cycle the arrow to User as shown below Select With AT Analoa Out Def User Press the Analog Out A or V key to cycle the arrow to User Press the Enter key You will then see the channel selection display as follows Select With A Anal o3 Out Source Press the A or W key to cycle the analog output source from channel X Y Z or Vector In this case we chose Channel Y Press the Enter key and observe the following display Enter Max outeut 1 5660 kG 3 18 Operation Lake Shore Model 460 Gaussmeter User s Manual Corrected Analog Out Continued Enter the numbers 1 5 on the numerical keypad and press the Enter key A maximum output of 1 5 kG has now been placed into memory Upon pressing Enter the following display will appear Enter Min outeut 1 5668 kG Enter the numbers 1
183. tion from the unit requesting service The SPD command ends the polling sequence Common Commands Common Commands are addressed commands which create commonalty between instruments on the bus All instruments that comply with the IEEE 488 1987 standard share these commands and their format Common commands all begin with an asterisk They generally relate to bus and instrument status and identification Common query commands end with a question mark 31 Model 460 common commands are detailed in Paragraph 4 3 1 and summarized in Table 4 8 Interface and Device Specific Commands Device specific commands are addressed commands The Model 460 supports a variety of device specific commands to program instruments remotely from a digital computer and to transfer measurements to the computer Most device specific commands perform functions also performed from the front panel Model 460 device specific commands are detailed in Paragraphs 4 3 2 thru 4 3 4 and summarized in Table 4 8 Message Strings A message string is a group of characters assembled to perform an interface function There are three types of message strings commands queries and responses The computer issues command and query strings through user programs the instrument issues responses Two or more command strings can be chained together in one communication but they must be separated by a semi colon Only one query is permitted per communication but it can be chained
184. tive is turned on for the X Y and Z channels but not the Vector channel the math defining the relative reading is as follows gt e 3 Xa A HY setpoint reading Axyz reading mone oO Zant Z setpoint This calculates the magnitude of a difference vector Difference in Magnitude of the Field Vector If the relative function is turned on for Vector Magnitude but not relative for the X Y or Z channels the math defining the relative reading is as follows D r 5 2 X 2 Leg 2 aw reading reading reading setpoint setpoint setpoint This provides the difference in magnitude of the field vector Therefore the two methods of relative calculation will cause different results to be displayed ALARM SET AND ALARM ON OFF The alarm gives an audible and visual indication of when the field value is either outside or inside a user specified range for that channel Before using the alarm function however the user must provide two settings that define the operating parameters of the alarms First is turning the audible alarm on or off Second is whether the alarm will be triggered by readings inside or outside the defined magnetic field range Default settings are audible alarm on and alarm will be triggered outside the low and high alarm setpoints These settings are accomplished by choosing a channel then pressing and holding the Alarm On Off key until the following display appears
185. to 0 C to e MFA 1815 VH 0 005 approx 400 Hz HSE 1 30 kG 75 C 0 09 G C 0 015 C Flexible_Axial eps Figure 5 10 Definition of Lake Shore Flexible Axial Probe 5 10 Accessories amp Probes Lake Shore Model 460 Gaussmeter User s Manual 5 4 HELMHOLTZ COIL LOW FIELD STANDARDS Lake Shore offers three Helmholtz coils 2 5 6 and 12 inch diameter Check the latest Lake Shore brochures or our website for any recent additions to this line These coils are accurately calibrated using field standards maintained at Lake Shore Most standards are traceable to physical standards such as a coil of carefully controlled dimensions or in some cases to proton resonance The field strengths are measured on the basis of the field generated by a current through the coil When combined with a customer supplied power supply these coils can be used as low field reference magnets to compliment our set of standard reference magnets defined in Paragraph 5 4 The power supply must be capable of 2 A output and a constant current mode is recommended MH 2 5 MH 6 MH 12 Inside Diameter 2 5 inches 6 inches 12 inches Field Accuracy 0 5 Field Strength x30G I1A x25G 1A Z12G 1A Field Homogeneity 0 5 within a 0 5 within a 0 5 within a cylindrical volume cylindrical volume cylindrical volume 0 75 long 0 75 1 6 long 1 6 3 2 long 3 2 diameter located at diameter located at diameter located at cent
186. to the end of a command The total communication string must not exceed 64 characters in length A command string is issued by the computer and instructs the instrument to perform a function or change a parameter setting When a command is issued the computer is acting as talker and the instrument as listener The format is lt command mnemonic gt lt space gt lt parameter data gt lt terminators gt Command mnemonics and parameter data necessary for each one is described in Paragraph 4 3 Terminators must be sent with every message string A query string is issued by the computer and instructs the instrument which response to send Queries are issued similar to commands with the computer acting as talker and the instrument as listener The query format is lt query mnemonic gt lt gt lt space gt lt parameter data gt lt terminators gt Query mnemonics are often the same as commands with the addition of a question mark Parameter data is often unnecessary when sending queries Query mnemonics and parameter data if necessary is described in Paragraph 4 3 Terminators must be sent with every message string Issuing a query does not initiate a response from the instrument A response string is sent by the instrument only when it is addressed as a talker and the computer becomes the listener The instrument will respond only to the last query it receives The response can be a reading value status report
187. ty dR dT is geometry dependent i e dR dT scales directly with R consequently this sensitivity is often normalized by dividing by the measured resistance to give a sensitivity st in percent change per kelvin st 100 R dR dT K where T is temperature in kelvin and R is resistance in ohms normally closed N C A term used for switches and relay contacts Provides a closed circuit when actuator is in the free unenergized position normally open N O A term used for switches and relay contacts Provides an open circuit when actuator is in the free unenergized position oersted Oe The cgs unit for the magnetic field strength H 1 oersted 10 n ampere meter 79 58 ampere meter ohm Q The SI unit of resistance and of impedance The ohm is the resistance of a conductor such that a constant current of one ampere in it produces a voltage of one volt between its ends pascal Pa The SI unit of pressure equal to 1 N m Equal to 1 45x10 psi 1 0197x10 5 kg em 7 5x10 torr 4 191x10 3 inches of water or 1x10 5 bar permeability Material parameter which is the ratio of the magnetic induction B to the magnetic field strength H u B H Also see Initial Permeability and Differential Permeability polynomial fit A mathematical equation used to fit calibration data Polynomials are constructed of finite sums of terms of the form aer where aiis the ith fit coefficient and vs some function of the dependent variable p
188. uery P e RELS Relative Mode Setpoint Cmd ACDC AC DC Field Reading Cmd RELS Relative Mode Setpoint Query ACDC AC DC Field Reading Query 9 Relative M int Multipli ALARM Alarm Function On Off Cmd Geer Er ultiplier ALARM Alarm Function On Off Query UNIT Gauss Tesla Units Query ALLF All Fields Query VSRC Vector Magnitude Source Cmd ALMB Audible Alarm Cmd 9 ALMB Audible Alarm Query VSRC Vector Magnitude Source Query ALMH Alarm High Point Cmd Probe Commands ALMH Alarm High Point Query FCOMP Field Compensation Cmd ALMHM Alarm High Point Multiplier Query FCOMP Field Compensation Query ALMIO Alarm Inside Outside Cmd ONOFF Probe On Off Cmd ALMIO Alarm Inside Outside Query ee Probe On Off Query ALML Alarm Low Point Cmd SNUM Probe Serial Number Query ALML Alarm Low Point Query Le Temp Compensation Cmd ALMLM Alarm Low Point Multiplier Query TCOMP Temp Compensation Query ALMS Alarm Status Query D E paints Remote Operation 4 23 Lake Shore Model 460 Gaussmeter User s Manual 4 3 1 Common Commands CLS Input Remarks KESE Input Format Remarks Example KESE Input Returned Format KESR Input Returned Format Remarks IDN Input Returned Format Example 4 24 Clear Interface Command CLS term Clears the bits in the Status Byte Register and Standard Event Status Register and terminates all pending operations Clears the interface but not the controller The relate
189. uring fields surrounding linear power supplies or solenoids driven at line frequency Peak circuitry in the Model 460 can capture single event peaks or monitor the peak amplitude of periodic wave forms Reproducible single peak measurements can be made down to 5 ms Three independent peak circuits allow simultaneous capture of all three inputs Instrument software enables an indefinite hold time with no decay Periodic peak measurements can be made over the same frequency range as RMS wave forms If faster peak or RMS measurements are required the Lake Shore Model 480 Fluxmeter has a wider frequency range Range and Resolution Hall effect gaussmeters are popular in part because of their ability to measure field over a broad range With appropriate probes the Model 460 has full scale ranges from 300 mG to 300 kG A different range can be used with each input With 5 4 digit resolution DC field variations approaching 0 010 mG can be detected In larger DC fields resolution of 1 part in 300 000 can be achieved RMS and peak measurements are limited to 4 digits or 1 part in 30 000 resolution because environmental noise is more difficult to separate from desired signal in those modes The filter feature can be used to improve resolution in noisy environments by taking a running average of field readings in DC or RMS modes Interface There are two computer interfaces included with the Model 460 parallel IEEE 488 and serial RS 232C Either interface
190. uss 10 gamma y e Both oersted and gauss are expressed as cm ge in terms of base units f A m was often expressed as ampere turn per meter when used for magnetic field strength g Magnetic moment per unit volume h The designation emu is not a unit i Recognized under SI even though based on the definition B oH J See footnote c j Uz Hoss 1 y all in SI pris equal to Gaussian p k Be H and poM H have SI units J m M H and B Hilda have Gaussian units erg cm R B Goldfarb and F R Fickett U S Department of Commerce National Bureau of Standards Bolder Colorado 80303 March 1985 NBS Special Publication 696 For sale by the Superintendent of Documents U S Government Printing Office Washington D C 20402 Units for Magnetic Properties B 1 Lake Shore Model 460 Gaussmeter User s Manual Table B 2 Recommended SI Values for Physical Constants E of Vacuum We e 4r x 107 Hm sevens Lin a 0 0073 Fine Structure Constant uOce2 2h 137 0360 Elementary Charge e 1 6022 x 10 19 i h 6 6262 x 10 34 J Hz Plank s Constant h h 2n 1 0546 x 10 J s Avogadro s Constant 6 0220 x 1073 mol Atomic Mass Unit 1 u 10 kg mol Na 1 6605 x 102 kg Ee EE EE eeipeteeet 13 mise Molar Volume Ideal Gas To 273 15K po 1 atm Data abbreviated to 4 decimal places from CODATA Bulletin No 11 ICSU CODATA Central Office 19 Westendstrasse 6 Frankfurt Main Germany Copies of this bulletin are
191. val CE Mark Ordering Information Part number Description Instrument 460 Model 460 Gaussmeter 3 V corrected analog output 460 10 Model 460 Gaussmeter 10 V corrected analog output Accessories Included 115 006 Detachable line cord U S 115 007 Detachable line cord European 4060 Zero gauss chamber MAN 460 Model 460 Gaussmeter User s Manual Accessories Available 4001 RJ 11 cable assembly 4002 RJ 11 to DB 25 adapter 4003 RJ 11 to DE 9 adapter 4004 IEEE 488 cable 1 meter 3 feet 4065 Large zero gauss chamber for Gamma probe RM 1 Rack mount kit for one 460 gaussmeter MCBL 6 User programmable cable with PROM 6 long MCBL 20 User programmable cable with PROM 20 long MPEC 10 Probe extension cable with EEPROM 10 long MPEC 25 Probe extension cable with EEPROM MPEC 50 Probe extension cable with EEPROM 50 long MPEC 100 Probe extension cable with EEPROM 100 long Extension cables must be matched to probes 25 long Probes Ordered Separately Custom Probes Available Consult Lake Shore for more information Specifications are subject to change without notice Introduction Lake Shore Model 460 Gaussmeter User s Manual 1 3 SAFETY SUMMARY Observe these general safety precautions during all phases of instrument operation service and repair Failure to comply with these precautions or with specific warnings elsewhere in this manual violates safety standards of design manufacture and intended instrum
192. ve a single fuse on the hot Units produced for International use have a double fuse for the hot and neutral To change line input from the factory setting use the appropriate fuse in the connector kit shipped with the instrument Test fuse with ohmmeter Do not rely on visual inspection of fuse WARNING To avoid potentially lethal shocks turn off gaussmeter and disconnect it from AC power before performing these procedures CAUTION For continued protection against fire hazard replace only w rating specified for the line for the line voltage selected Turn power switch Off O Remove instrument power cord oP ONS 100 120 V 220 240 V 1AT250V 0 5 A T 250 V 0 25 x 1 25 inches 5 x 20 mm Re assemble line input assembly in reverse order Verify voltage indicator in the line input assembly window Connect instrument power cord o NoD Turn power switch On I Service ith the same fuse type and Locate line input assembly on the instrument rear panel See Figure 6 1 With a small screwdriver release the drawer holding the line voltage selector and fuse Remove existing fuse s Replace with proper Slow Blow fuse ratings as follows 6 3 6 5 6 4 Lake Shore Model 460 Gaussmeter User s Manual REAR PANEL CONNECTOR DEFINITIONS The connectors on the rear panel of the Model 460 Gaussmeter are detailed in Figures 6 2 thru 6 4 Additional details for the IEEE 488 connector is provided in P
193. ware required to produce and implement these programs not included with the instrument the concepts illustrated apply to almost any application where these tools are available 4 2 7 1 Visual Basic Serial Interface Program Setup The serial interface program Table 4 5 works with Visual Basic 6 0 VB6 on an IBM PC or compatible with a Pentium class processor A Pentium 90 or higher is recommended running Windows 95 or better with a serial interface It uses the COM1 communications port at 9600 Baud Use the following procedure to develop the Serial Interface Program in Visual Basic 1 Start VB6 2 Choose Standard EXE and select Open 3 Resize form window to desired size 4 On the Project Menu click Components to bring up a list of additional controls available in VB6 5 Scroll through the controls and select Microsoft Comm Control 6 0 Select OK In the toolbar at the left of the screen the Comm Control will have appeared as a telephone icon 6 Select the Comm control and add it to the form 7 Add controls to form a Add three Label controls to the form b Add two TextBox controls to the form c Add one CommandButton control to the form d Add one Timer control to the form 8 On the View Menu select Properties Window 9 Inthe Properties window use the dropdown list to select between the different controls of the current project Label Command ig Serial Interface Program Label3 Label 10 Set the prope
194. win H Hall 1855 1938 an American physicist Hall mobility The quantity un in the relation uH Ro where R Hall coefficient and o conductivity Helmholtz coils A pair of flat circular coils having equal numbers of turns and equal diameters arranged with a common axis and connected in series used to obtain a magnetic field more nearly uniform than that of a single coil hertz Hz A unit of frequency equal to one cycle per second hole A mobile vacancy in the electronic valence structure of a semiconductor that acts like a positive electron charge with a positive mass 7 hysteresis The dependence of the state of a system on its previous history generally in the form of a lagging of a physical effect behind its cause Also see magnetic hysteresis IEEE Institute of Electrical and Electronics Engineers IEEE 488 An instrumentation bus with hardware and programming standards designed to simplify instrument interfacing The addressable parallel bus specification is defined by the IEEE initial permeability The permeability determined at H 0 and B 0 initial susceptibility The susceptibility determined at H 0 and M 0 integrator A circuit or network whose output waveform is the time integral of its input waveform international system of units SI A universal coherent system of units in which the following seven units are considered basic meter kilogram second ampere kelvin mole and candela The International
195. wly changing signals A field change not visible on the display can not be recorded in DC Max Hold The display shows only the magnitude of the maximum reading In AC RMS operation the maximum RMS value displayed is held i e operates the same as DC Max In AC Peak operation a hardware circuit traps peaks in the Hall voltage In this mode the unit displays the magnitude of the highest peak of an impulse or event For best accuracy the event must be at full amplitude for at least a few milliseconds In the case of the Vector Magnitude display turning on Max Hold will cause the vector source display to be replaced with MAX Turning on Max Hold for Vector Magnitude means the maximum value calculated will be displayed It does not mean each of the individual component max hold readings are used to form the Vector Magnitude display When Max Hold for the Vector Magnitude is turned off but Max Hold for the X Y or Z channels is on the individual maximums are for display only and are not used for the calculation of the Vector Magnitude display ZERO PROBE The zero probe function is used to null cancel out the zero offset of the probe or small magnetic fields It is normally used in conjunction with the zero gauss chamber but may also be used with an unshielded probe registering the local earth magnetic field If three separate probes are being used each probe may be independently zeroed For the three axis probes each axis may be independent
196. x Hold value A Relative reading k Remote operation A Alarm on 1 4 Keypad 25 full travel keys Front Panel Features Intuitive operation display prompts front panel lockout brightness control Interfaces RS 232C Capabilities Baud 300 1200 9600 Connector RJ 11 configuration Update Rate Up to 14 readings per second IEEE 488 Capabilities Complies with IEEE 488 2 SH1 AH1 SR1 RL1 PPO DC1 DTO Co E1 Software Support LabView Driver Update Rate 18 rdgs sec Vector Off 14 rdgs sec Vector On Alarm Settings High and low set point Inside Outside Audible Actuators Display annunciator beeper Monitor Analog Output 3 Configuration Real time analog voltage output Scale 3 V FS on selected range Frequency Response DC to 400 Hz Accuracy Probe dependent Minimum Load Resistance 1 kQ short circuit protected Connector BNC Corrected Analog Output 1 Configuration Voltage output generated by DAC Range 3 V 10 V for Model 460 10 Scale User defined Resolution 0 366 mV of 3 V Update Rate Same as field measurement Accuracy 0 1 of full scale in addition to measurement error Minimum Load Resistance 1 kQ short circuit protected Connector BNC General Ambient Temperature 15 35 C at rated accuracy 5 40 C with reduced accuracy Power Requirement 100 120 220 240 VAC 5 10 50 or 60 Hz 40 watts Size 434 W x 89 H x 369 mm D 17 1 x 3 5 x 14 5 in half rack Weight 7 5 kilograms 16 5 pounds Appro
197. y See Magnetic Flux Density baud A unit of signaling speed equal to the number of discrete conditions or signal events per second or the reciprocal of the time of the shortest signal element in a character bit A contraction of the term binary digit a unit of information represented by either a zero or a one calibration To determine by measurement or comparison with a standard the correct accurate value of each scale reading on a meter or other device or the correct value for each setting of a control knob Glossary of Terminology A 1 Lake Shore Model 460 Gaussmeter User s Manual cathode The terminal from which forward current flows to the external circuit 2 Anode cathode Celsius C Scale A temperature scale that registers the freezing point of water as 0 C and the boiling point as 100 C under normal atmospheric pressure Celsius degrees are purely derived units calculated from the Kelvin Thermodynamic Scale Formerly known as centigrade See Temperature for conversions cgs system of units A system in which the basic units are the centimeter gram and second coercive force coercive field The magnetic field strength H required to reduce the magnetic induction B ina magnetic material to zero coercivity generally used to designate the magnetic field strength H required to reduce the magnetic induction B ina magnetic material to zero from saturation The coercivity would be the
198. y two captive locking screws with metric threads The total length of cable allowed in a system is 2 meters for each device on the bus or 20 meters maximum A system may be composed of up to 15 devices Figure 6 5 shows the IEEE 488 Interface connector pin location and signal names as viewed from the Model 460 rear panel IEEE 488 INTERFACE SH1 An T5 L4 SEI RLI PPO DC1 DTO CO E1 C 460 6 5 eps DESCRIPTION Data Input Output Line 1 Data Input Output Line 2 Data Input Output Line 3 Data Input Output Line 4 End Or Identify Data Valid Not Ready For Data Not Data Accepted Interface Clear Service Request Attention Cable Shield Data Input Output Line 5 Data Input Output Line 6 Data Input Output Line 7 Data Input Output Line 8 Remote Enable Ground Wire Twisted pair with DAV Ground Wire Twisted pair with NRFD Ground Wire Twisted pair with NDAC Ground Wire Twisted pair with IFC Ground Wire Twisted pair with SRQ Ground Wire Twisted pair with ATN Logic Ground Figure 6 5 IEEE 488 Rear Panel Connector Details Service 6 5 Lake Shore Model 460 Gaussmeter User s Manual 6 6 OPTIONAL SERIAL INTERFACE CABLE AND ADAPTERS To aid in Serial Interface troubleshooting Figures 6 6 thru 6 8 show wiring information for the optional cable assembly and the two mating adapters o a T mb YELLOW N Cna _ _ GREEK S C T deg EE e N el RD o BLACK we o C 460 6 6 eps Figure 6 6
199. ypes Be cautious about using aluminum stemmed transverse probes such as the Model MMT 6J08 type where AC magnetic fields are to be measured Eddy currents in the stem material can affect reading accuracy A superior choice for AC measurements would b the Model MNT 4E04 type fiberglass epoxy stem probes Several stem lengths are offered for each probe type User preferences or test set up dimensions usually determine the final selection Longer stems are more susceptible to accidental bending in many cases not catastrophic but bothersome Stem length does not affect performance Be aware of the differences in the probe active areas shown on the data sheet A Hall effect probe will indicate the average field value sensed over that total active area Thus when measuring magnetic fields with a high gradient across the sensor width choose the smallest active area practical keeping in mind however the fragility rule in number 2 above Lake Shore gaussmeter probes exhibit different ranges of magnetic fields over which they will provide valid readings Check the specification sheet for these usable ranges High Stability probes such as those whose model numbers end in VG are usable on full scale ranges of 300 gauss 30 millitesla to 30 kilogauss 3 tesla The High Sensitivity family of probes e VH models can be used on 30 G 3 mT to 30 kG 3 T full scale ranges High field probes are specially calibrated to provide use above 30

Manual - Lake Shore Cryotronics, Inc.

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