Omega 871A, Руководство пользователя

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Figure 4-2. Access to Calibration Adjustments
TABLE 4-3
CALIBRATION ADJUSTMENTS FOR MODEL 871A
4.3 CALIBRATION FOR MODEL 872A
4.3.1 Equipment Needed
1. DC voltage calibrator with ±0.01% of setting and ± 20 µV accuracy.
2. 100: 1 divider: 1.98 kilohm and 20 ohm wirewound resistors with 0.02%
ratio accuracy or better.
3. OMEGA TRC III Ice Point Reference Chamber or distilled water ice bath.
4. OMEGA type J TRP Reference Probe or make a thermocouple
transition junction (see paragraph 4.3.3).
4.3.2 Environmental Conditions
To meet all specifications, the conditions for calibration should be: an
ambient temperature of 23º ± 1ºC; relative humidity less than 80%.
4.3.3 Setup
1. To make a thermocouple transition junction, silver solder a piece of
copper wire to each (type J) thermocouple wire and insulate the
junction with a waterproof jacket.
2. Connect the thermocouple wires from the type J transition junction to
an OMEGA miniature connector SMP-J-M.
8
871 Calibrator Trimmer Desired
Step Adjustment Range Setting (V) Adjust Reading
1 Input Offset Null 220ºC 0.0000 R109 00.0ºC
2 + Gain (X1) 1370ºC 5.3039 R104 1320ºC
3 + Gain (X10) 200ºC 0.6939 R105 170.0ºC
4 - Gain 200ºC -0.1527 R103 -40.0ºC
5 ºF Offset 200ºF 0.000 R102 32.0ºF