Table 6: Calibration of Calibrator-Mode Resistance Functions (RTD-Thermistor)

 

 

 

Current

 

 

 

 

Sensor

Unit

Source

 

 

DMM

Step

Select

Output

Input

Adjust

Verify

Reading*

1

RTD-100

1562.0°F

1mA

P38

0.39026v

2

RTD-100

32.0°F

1mA

 

0.10000

 

 

 

 

 

±0.00006v

3

RTD-100

–328.0°F

1mA

 

0.01849

 

1,000Ω

900.00Ω

 

 

±0.00012v

4

1mA

 

0.90000

 

1,000Ω

1.00Ω

 

 

±0.00020v

5

1mA

 

0.00100

 

100,000Ω

90,000Ω

 

 

 

±0.00020v

6

10µA

P51

 

0.90000v

7

100,000Ω

100Ω

10µA

 

0.00100

 

 

 

 

 

±0.00020v

8

Thermistor

293.0°F

1mA

 

0.04700

 

 

 

 

 

±0.00020v

9

Thermistor

77.0°F

10µA

 

0.02252

 

 

 

 

 

±0.00020v

10

Thermistor

–40.0°F

10µA

 

0.75790

 

 

 

 

 

 

±0.00500v

 

 

 

 

 

 

 

* exclusive of noise.

 

 

 

 

 

2. CALIBRATION VERIFICATION

Calibration is verified with the same instrument hookups as used for calibra- tion (ie. Figures 12 and 13 for thermocouple functions, Figure 14 for resis- tance functions).

While one hookup serves to verify all resistance functions (RTD, thermistor, ohms), a full check-out of thermocouple functions requires a set of calibration cables for each thermocouple type.

To simplify the verification of thermocouple calibration, software has been enhanced to reactivate the copper-mode used during calibration. This feature is available on products that use the following (and later) software revisions:

32

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Image 34
Omega 26, 27, 25, 24 manual Calibration Verification