background image

Lake Shore Model 231 User’s Manual 

 

 

ii 

Table of Contents 

TABLE OF CONTENTS (Continued) 

 

Chapter/Paragraph 

Title 

Page 

OPTIONS AND ACCESSORIES ................................................. 5-1 

5.0 

General .......................................................................... 5-1 

5.1 

Enclosures ..................................................................... 5-1 

5.2 

Options........................................................................... 5-1 

5.3 

Accessories .................................................................... 5-2 

5.4 

Wires .............................................................................. 5-2 

5.5 

Sensors .......................................................................... 5-3 

5.6 

Special Equipment ......................................................... 5-3 

APPENDIX A 

– MODEL 231 CURVE TABLES ................................. A-1 

APPENDIX B 

– GLOSSARY OF TERMINOLOGY ............................ B-1 

 

 

LIST OF ILLUSTRATIONS 

 

Figure No. 

Title 

Page 

1-1 

Typical Model 231 Front Panel.............................................. 1-2 

1-2 

Single Enclosure Case Physical Dimensions ........................ 1-6 

1-3 

Multiple Unit Case Physical Dimensions ............................... 1-8 

2-1 

Typical Wall Plug-In Power Supply ....................................... 2-7 

3-1 

Model 231 DIP Switch (S1) ................................................... 3-1 

4-1 

Front Panel Connectors J2 & J3 Details ............................... 4-2 

4-2 

VMEbus Connector J1 Details .............................................. 4-3 

4-3 

Model 231 PCB Layout ......................................................... 4-4 

 
 

LIST OF TABLES 

 

Table No. 

Title 

Page 

1-1 

Model 231 Input Specifications ............................................. 1-3 

1-2 

Model 231P Input Specifications ........................................... 1-4 

1-3 

Model 231 & 231P Output Specifications .............................. 1-5 

1-4 

Model 2308-12 VMEbus Rackmount Case Specs ................ 1-7 

2-1 

Effect of Current Variation on Diode Temperature ................ 2-5 

2-2 

Typical DT-470 dV/dI Values for Selected Temps ................. 2-5 

3-1 

Conversion Parameters for Temperature in K ....................... 3-2 

A-1 

Lake Shore Standard Diode Curves ......................................A-1 

A-2 

Series PT-100 Platinum Resistance Curve ...........................A-2 

 

Summary of Contents for 231

Page 1: ...A E Mail 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 righ...

Page 2: ...duct 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 7 To the extent allowed by applicable la...

Page 3: ...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 calibration 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 Bur...

Page 4: ......

Page 5: ...Lake Shore Model 231 User s Manual ...

Page 6: ......

Page 7: ...ur Lead Measurements 2 3 2 3 2 Connecting Leads To The Sensor 2 3 2 3 3 Sensor Mounting 2 3 2 3 4 Measurement Errors Due To AC Noise 2 4 2 4 Sensor Curve Definition 2 5 2 5 Power Connections 2 6 3 OPERATION 3 1 3 0 General 3 1 3 1 PCB DIP Switch Settings 3 1 3 2 Output to Temperature Conversion 3 2 4 SERVICE 4 1 4 0 General 4 1 4 1 General Troubleshooting 4 1 4 1 1 No Output On Board LED Off 4 1 4...

Page 8: ...ltiple Unit Case Physical Dimensions 1 8 2 1 Typical Wall Plug In Power Supply 2 7 3 1 Model 231 DIP Switch S1 3 1 4 1 Front Panel Connectors J2 J3 Details 4 2 4 2 VMEbus Connector J1 Details 4 3 4 3 Model 231 PCB Layout 4 4 LIST OF TABLES Table No Title Page 1 1 Model 231 Input Specifications 1 3 1 2 Model 231P Input Specifications 1 4 1 3 Model 231 231P Output Specifications 1 5 1 4 Model 2308 1...

Page 9: ...for use within either of two enclosures a Model 2308 1 single space enclosure or a Model 2308 12 rackmount case that holds up to 12 units The Model 231 Temperature Transmitter sends temperature data from its position near a sensor to a data acquisition channel or strip chart recorder It operates with Silicon diode or Gallium Aluminum Arsenide GaAlAs diode sensors Lake Shore Silicon diode sensors a...

Page 10: ...o a voltage reading scaled from zero A 500 0 02 precision resistor is provided for this purpose This resistor produces the maximum full scale output of 10 V A single 5 VDC supply powers Model 231 circuitry The outputs are isolated so several 231s can operate from the same supply without interference The 5 VDC can also be supplied from the pins on the VME bus connector Mechanical mounting is easy b...

Page 11: ...ensor Sensitivity 30 mV K at 4 2 K 1 9 mV K at 77 35 K 2 4 mV K at 300 K Measurement Resolution Sensor Units 76 3 µV Temp Equivalence 2 5 mK at 4 2 K 40 mK at 77 35 K 32 mK at 300 K Measurement Accuracy Sensor Units 75 µV 0 01 of reading Temp Accuracy 0 07 K at 4 2 K 0 16 K at 77 35 K 0 12 K at 300 K DT 470 CO with 8001 CalCurve Measurement Temperature Coefficient Sensor Units 0 0006 of voltage re...

Page 12: ...mperature Range 14 K 873 K with PT 103 Standard Curve DIN 43760 Typical Sensor Sensitivity 0 19 K 30 K 0 42 K 77 35 K 0 39 K 300 K 0 34 K typical up to 800 K Measurement Resolution Sensor Units 4 8 m Temp Equivalence 22 mK at 30 K 11 mK at 77 35 K 13 mK at 300 K 14 mK typical up to 800 K Measurement Accuracy Sensor Units Ohms Temp Accuracy 0 2 K at 30 K 0 15 K at 77 35 K 0 3 K at 300 K 0 7 K typic...

Page 13: ...ull scale Temp Equivalence 0 20 K 2 5 mK 0 325 K 41 mK 0 100 K 12 5 mK 0 475 K 59 mK 0 200 K 25 mK 0 1000 K 125 mK Output Temperature Coefficient Current output C ambient 0 0055 C Temp Equivalence 0 20 K 1 mK C 0 325 K 18 mK C 0 100 K 6 mK C 0 475 K 26 mK C 0 200 K 12 mK C 0 1000 K 55 mK C 0 20 mA Output 0 10 V w 500 0 02 Load Resistor Output Resolution Voltage 0 6 mV 0 006 of full scale Temp Equi...

Page 14: ...ng VME end panel and back plane Transmitter does not use electrical bus format only its physical shape and power supply Note Electronic temperature accuracy in a given temperature range is the sum of temperature accuracies of input and output Sensor calibration errors are not included 1 2 SINGLE ENCLOSURE CASE DESCRIPTION Holds one Model 231 Typical dimensions appear below Figure 1 2 Typical Singl...

Page 15: ... to Paragraph 2 5 for further information on the built in power supply CAUTION The Model 2308 12 bus is designed only to power multiple Model 231s Do not use with standard VME cards Table 1 4 Model 2308 12 VMEbus Rackmount Case Specifications No of Card Slots 12 Size 45 17 8 26 centimeters 17 7 7 10 25 inches Weight 5 5 kilograms 12 pounds Output Voltage 5 VDC 100 mV Peak to Peak Ripple Output Cur...

Page 16: ...Lake Shore Model 231 User s Manual 1 8 Introduction Figure 1 3 Typical Multiple Unit Case Physical Dimensions ...

Page 17: ...nd 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 immediately behind the title page 2 2 REPACKAGING FOR SHIPMENT To return the Model 231 or accessories for repair or replacement obtain a Return Goods Au...

Page 18: ...ince heat flow down the leads can be critical in a cryogenic environment wire of small diameter and significant resistance per foot is preferred to minimize this heat flow Consequently a voltage drop within the leads may exist Four lead measurement confines current to one pair of leads and measures sensor voltage with the other lead pair carrying no current 2 3 1 1 Two Lead Measurement Sometimes s...

Page 19: ...or Manganin wire is commonly used in sizes 32 or 36 AWG These wires have a fairly low thermal conductivity yet electrical resistance is not large enough to create measurement problems Thermally anchor lead wires at several temperatures between room temperature and cryogenic temperatures to guarantee no heat conduction through the leads to the sensor 2 3 3 Sensor Mounting Before installing a diode ...

Page 20: ...t mountings use Stycast epoxy instead of Apiezon N Grease NOTE Do not apply Stycast epoxy over the DT 470 SD package sensor stress may shift the readings In all cases periodically inspect the sensor mounting to verify good thermal contact to the mounting surface is maintained For the Model 231P Series PT 100 Platinum Sensors follow the same basic procedures for diode type sensors However Platinum ...

Page 21: ...or 36 AWG Lake Shore Duo Twist Cryogenic Wire which features phosphor bronze wire twisted at 3 15 twists per centimeter 8 twists per inch Refer to the Lake Shore Product Catalog or contact Lake Shore for further information 2 4 SENSOR CURVE DEFINITION Model 231 sensor curves include Curve 10 DT 670 Platinum Curve DIN 43760 and a factory installed CalCurve for a calibrated sensor After selecting th...

Page 22: ... a currently owned Lake Shore calibrated sensor Lake Shore requires the sensor model number and serial number at the time of order The Model 8002 231 is for field installations of the CalCurve in an existing Model 231 The CalCurve is required with a Lake Shore TG 120 Series Gallium Aluminum Arsenide Diode Temperature Sensor 2 5 POWER CONNECTIONS The Model 231 is powered by the 5 VDC supply in the ...

Page 23: ...ion 2 7 The Model 2308 10 VMEbus rackmount case has a built in power supply for up to twelve Model 231s The built in power supply has a universal input 85 to 265 VAC 47 to 440 Hz 60 watts C 231 2 1 eps Figure 2 1 Typical Wall Plug In Power Supply ...

Page 24: ...Lake Shore Model 231 User s Manual 2 8 Installation This Page Intentionally Left Blank ...

Page 25: ...er should be enabled on the Model 231 PCB DIP Switch S1 See Figure 3 1 Select only one range at a time The range is enabled when the switch is closed ON Units ship from the factory with the DIP switch set to RANGE4 closed 0 to 325 K For the Model 231 set the CURVE switch to open for the DT470 Curve 10 or the CalCurve option if present or closed for the DT 670 Curve For the Model 231P set the CURVE...

Page 26: ...current or voltage is directly proportional to the temperature reading For the 4 20 mA output the following formula converts output current to temperature T A B x IOUT where T temperature in kelvin IOUT output current in mA and A and B are constants from Table 3 1 depending on temperature For the 0 20 mA output using the included 500 resistor for 0 10 V the following formula converts output voltag...

Page 27: ...fy that OUT and SHIELD are not connected to each other Due to extensive protection circuitry installed in Model 231 all the above problems eventually cause the 0 5 A slow blow fuse to burn out After correction replace the blown fuse with identical size and type 4 1 2 Output Stops Before Reaching Upper Limit Normally caused by too high resistance of output monitoring device Absolute maximum accepta...

Page 28: ... connections may be open If sensor voltage polarity is negative SENS V and SENS V leads are reversed With the sensor at operating temperature the voltage readings should correspond to Curve 10 for diode sensors or DIN 43760 for platinum sensors as detailed in Appendix A 4 2 MODEL 231 CONNECTORS There are three connectors on the Model 231 The two front panel connectors are the 8 pin terminal block ...

Page 29: ...igure 4 3 for the Model 231 PCB layout Allow 5 minutes warm up before calibration 4 3 1 Required Test Equipment 1 A digital voltmeter DVM that measures DC voltage between 0 and 10 V accurately to 0 0001 V 2 A regulated 5 V DC power supply with tolerance within 0 25 V capable to source 500 mA on an S 760 or S 765 Switchcraft or equivalent power plug 0 218 inch outside diameter accepts 0 08 inch dia...

Page 30: ...Perform this reference calibration before output calibration 1 Connect DVM negative lead to Model 231 reference ground REF GND on TP2 and positive lead to VREF on TP3 2 Adjust trimpot R33 VREF TRIM until DVM reads 2 5000 V 0 0001 V P 231 4 3 bmp Figure 4 3 Model 231 PCB Layout ...

Page 31: ...s 1 and 2 in place 7 DVM reading should drop to about 0 V Allow 10 seconds for reading to stabilize 8 Adjust trimpot R25 OUTPUT OFFSET until DVM reading is between 0 and 0 0001 V 9 Remove jumper wire 3 between V and V Leave Jumpers 1 and 2 in place 10 DVM reading should be about 10 V 11 Adjust trimpot R27 OUTPUT GAIN until DVM reading is 10 0000 0 0001 V 12 Re check offset calibration Step 8 and a...

Page 32: ...Lake Shore Model 231 User s Manual 4 6 Service This Page Intentionally Left Blank ...

Page 33: ...e with built in power supply for up to 12 Model 231s 5 2 OPTIONS Model Description Of Option 8001 231 Factory Installed CalCurve Allows instrument to more accurately use the calibration data to calculate and output current proportional to temperature Requires a calibrated sensor 8002 231 Field Installed CalCurve Requires field installation of a new microprocessor memory IC Allows instrument to mor...

Page 34: ... 0 02 5 4 WIRES P N Description Of Cable 9001 005 Quad Twist Cryogenic Wire Two twisted pairs phosphor bronze wire 36 AWG 0 127 mm 0 005 inch diameter 9001 006 Duo Twist Cryogenic Wire Single twisted pair phosphor bronze wire 36 AWG 0 127 mm 0 005 inch diameter 9001 007 Quad Lead Cryogenic Wire Phosphor bronze wire flat 32 AWG 0 203 mm 0 008 inch diameter 9001 008 Quad Lead Cryogenic Wire Phosphor...

Page 35: ... surfaces Series DT 470 Silicon Diode Temperature Sensor Interchangeable repeatable accurate wide range customized for cryogenics Series DT 471 An economical version of the DT 470 for applications where temperature measurements below 10 K are not required Series DT 670 Lake Shore s newest silicon diode temperature sensor Interchangeable repeatable accurate wide range customized for cryogenics Seri...

Page 36: ...Lake Shore Model 231 User s Manual 5 4 Options Accessories This Page Intentionally Left Blank ...

Page 37: ...0 0 14703 0 21870 0 32600 0 49026 0 59422 0 67357 0 75123 0 81604 0 86861 0 90948 0 94910 0 98709 1 01423 1 04026 1 06998 1 09543 1 10612 1 11272 1 11566 1 11945 1 12592 1 14082 1 18219 1 27532 1 33400 1 41020 1 59237 1 63785 1 64411 6 55360 499 9 475 0 460 0 435 0 390 0 340 0 280 0 230 0 195 0 165 0 140 0 115 0 95 0 77 4 60 0 44 0 36 0 31 0 28 0 27 0 26 0 25 0 24 0 20 0 15 5 12 0 9 0 3 8 2 0 1 4 ...

Page 38: ...dT K K 14 0 20 0 30 0 40 0 50 0 70 0 100 0 150 0 200 0 300 0 400 0 500 0 600 0 700 0 800 0 900 0 1000 0 1 797 2 147 3 508 5 938 9 228 17 128 29 987 50 815 71 073 110 452 148 616 185 035 221 535 256 243 289 789 322 176 353 402 0 035 0 084 0 190 0 291 0 361 0 414 0 411 0 405 0 399 0 388 0 376 0 364 0 353 0 341 0 330 0 318 0 306 1 32 1 17 0 92 0 67 0 43 0 93 1 43 1 93 2 43 2 93 3 43 3 93 0 55 0 48 0 ...

Page 39: ...ent flows to the external circuit 2 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 ce...

Page 40: ...latively 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 2 hazard communication standard HCS The OSHA standard cited in 29 CFR 1910 1200 requiring communic...

Page 41: ... Nonflammable Gas DOT Class Nonflammable Gas DOT Name Nitrogen Refrigerated Liquid DOT ID No UN 1977 material safety data sheet MSDS OSHA Form 20 contains descriptive information on hazardous chemicals under the OSHA Hazard Communication Standard HCS These data sheets also provide precautionary information on the safe handling of the gas as well as emergency and first aid procedures MKSA System of...

Page 42: ...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 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 3...

Page 43: ......

Reviews: