Omega 871A, Руководство пользователя

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4.1.2 Accuracy Check
1. Prepare a pure-water ice bath (see paragraph 4.2.3, step 5).
2. Connect a thermocouple probe to input 1 of the unit.
3. Immerse the probe into the pure-water ice bath and allow ten
minutes for thermal stabilization.
4. Turn on the instrument and use Tables 4-1 and 4-2 to verify
that the readings on each range are within specification.
TABLE 4-1
MODEL 871A RANGE CHART
TABLE 4-2
MODEL 872A RANGE CHART
4.2 CALIBRATION FOR MODEL 871A
4.2.1 Equipment Needed
1. DC Voltage Calibrator with 1 ±0.01% of setting ± 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 K TRP Reference Probe or make a thermocouple transi-
tion junction (see paragraph 4.2.3).
4.2.2 Environmental Conditions
To meet all specifications, the conditions for calibration should be an
ambient temperature 23º ± 1ºC; relative humidity less than 80%.
Range Allowable Reading
2000°F 32° ± 2°
200°F 32.0° ± 1.8°
1370°C 0° ± 1°
200°C 0.0° ± 1.0°
Range Allowable Reading
1400°F 32° ± 2°
200°F 32.0° ± 1.8°
760°C 0° ± 1°
200°C 0.0° ± 1.0°
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