Measurement Computing CB-COM-7021 - Manual (Page 16)

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CB-7021, CB-7022, CB-7024 User’s Manual
1.9 Calibration
Don’t Perform Calibration Until You Understand Procedure.
CB-7021/21P Current Output Calibration Sequence:
1.
Set the jumper 1 to internal power and connect milliammeter
to module’s current output. If a milliammeter in not available,
use Volt Meter with shunt resistor (250 ohms, 0.1%). Calculate
the output current by the Volt Meter value (I = V/250).
2. Warm-Up for 30 minutes.
3. Setting type to 30. (0 to 20 mA) Refer Sec. 2.1.
4. Program output for 4 mA. Refer Sec. 2.7.
5. Check the meter and trim the output until
4 mA match by apply trim command. Refer Sec. 2.10.
6. Preform 4 mA Calibration Command. Refer Sec. 2.8.
7. Program output for 20 mA. Refer Sec. 2.7.
8. Check the meter and trim the output until
20 mA obtained by trim command.
Refer Sec. 2.10
9. Perform 20 mA Calibration Command. Refer Sec. 2.9.