Lightwave Communications LDT-5525 manual Table B.2 10K Thermistor Temperature Range

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C H A P T E R B

Thermistor Range

thermistor inputs of the LDT-5525. The LDT-5525's measurement system will over-range when the input voltage exceeds about 4.5 volts. Figure B.1 graphically shows the lower temperature and upper voltage limits for a typical 10 K thermistor. (A 10 K thermistor has a resistance of 10 kΩ at 25 oC). The practical temperature ranges for a typical 10 K thermistor with the LDT-5525 are given in Table B.2, below. These temperature ranges may vary from thermistor to thermistor, even though both thermistors are nominally 10 K. This is due to manufacturing tolerances in the thermistor, and is compensated for by determining C1, and C2 (calibrating the thermistor). The practical temperature ranges for a 10 K thermistor are also shown as solid bars at the bottom of Figure B.1.

Table B.2 10K Thermistor Temperature Range

 

 

 

 

SENSING CURRENT

TEMPERATURE RANGE

 

 

 

 

10 µA

-30 to 30 oC

 

 

 

 

 

 

100 µA

10 to 70 oC

 

 

 

 

 

 

 

 

(USING TYPICAL* 10 Ωk

o

C THERMISTOR)

 

 

5.00

 

@ 25

 

 

 

 

 

 

 

 

 

 

4.50

 

 

 

 

 

 

 

 

4.00

 

 

 

 

 

 

 

 

3.00

 

 

 

 

 

 

 

 

THERMISTOR

 

 

 

 

 

 

 

 

VOLTAGE

 

 

 

 

 

 

 

 

2.00

 

 

 

 

 

 

 

 

1.00

 

 

 

 

 

 

 

 

0.00

 

 

 

 

 

 

 

 

-60

-40

-20

0

20

40

60

80

100

 

 

 

DEGREES C

 

 

 

 

 

 

 

 

 

 

10µ A

 

 

 

 

 

 

 

 

 

 

100 µ A

 

 

 

 

- Denotes practical range with typical 10K thermistor

* ILX default values for C1 and C2

 

- Denotes measurable range with typical 10K thermistor

Figure B.1 Thermistor Temperature Range

 

34 LDT-5525

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Contents User’s Guide Page Table of Contents Appendix a Steinhart-Hart Equation Appendix C AD590 and LM335 Sensor Calibration Iv LDT-5525 List of Figures Vi LDT-5525 Safety Information and the Manual General Safety ConsiderationsSafety Symbols Safety Marking SymbolsWarranty Claims for Shipping Damage Comments, Suggestions, and Problems When you contact us, please have the following informationXii LDT-5525 Introduction and Specifications Product OverviewAvailable Options and Accessories Description Model NumberSpecifications Output1User Calibration General Specifications LDT-5525 AC Power Considerations OperationRack Mounting Power-Up Sequence Introduction to the LDT-5525 Front PanelAdjustments Sensor CAL Output Sensor Select Switch Back Panel Controls and ConnectionsTEC Connector Back Panel TEC ConnectorTEC Grounding Considerations General Operating Procedures Temperature Mode OperationWarm-Up and Environmental Considerations Resistance Mode Operation External Safety Switch OperationBooster Operation General Operating Procedures LDT-5525 Maintenance and Troubleshooting Calibration OverviewRecommended Equipment Environmental ConditionsWarm Up Calibration Adjustments Thermistor CalibrationAD590 Sensor Calibration LM335 Sensor Calibration ITE Current Calibration Troubleshooting Symptom Causes and Corrective ActionsTemperature, based on C1 and C2 STEINHART-HART Equation Table A.1 Comparison of Curve Fitting EquationsThermistor R/T Curves Computer Program REM Print Using H$ I, TI, RI LDT-5525 Sensing Current Thermistor Selection Thermistor RangeTable B.2 10K Thermistor Temperature Range Temperature Resolution Selecting and Using ThermistorsSelecting the Sensing Current Thermistor Range AD590 and LM335 Sensor Calibration AD590 SensorLM335 Sensor Figure C.1 AD590 Nonlinearity0607 One Point Calibration Method Two Point Calibration MethodC1n = U + V * C1 and C2n = V * C2 LDT-5525