Test Considerations; Performance Tests; Volts Dc Verification - Fluke 8845A Calibration Manual

Test Considerations

For optimum performance, all test procedures should comply with the following
recommendations:
•
Assure the calibration ambient temperature (T
28 °C. Ideally the calibration should be performed at 23 °C ±2 °C.
•
Assure ambient relative humidity is less than 80%.
•
Allow a 60-minute warm-up period.
•
Use shielded twisted-pair PTFE-insulated cables to reduce settling and noise
errors.
•
Keep all input cables as short as possible.
•
Ensure that the calibration standards and test procedures used do not introduce
additional errors.
Ideally, the standards used to verify and adjust the Meter should be four
times more accurate than each full-scale error specification of the Meter.
•
User Fluke's low thermal 4-Wire short for all voltages and ohmic shorts. See
Table 3-1 for Fluke part number..

Performance Tests

The following performance tests are provided to ensure that the Meter is in proper
operating condition. If the Meter fails any of the performance tests, calibration
adjustment and/or repair is needed. The performance test works best if executed in the
sequence shown in Table 3-2.
Each of the measurements listed in the following tests assumes the Meter is being tested
after a one-hour warm-up in an environment with an ambient temperature of 18 to 28ºC
and a relative humidity of less than 80%.

Volts DC Verification

Connect the Meter to the test equipment as shown in Figure 3-1 and, depending on which
meter you are calibrating, apply the voltages listed in Table 3-2 or Table 3-3. Verification
forms can be found in Appendix A which can be copied and used to record each meter
reading.
For the zero (0) V tests, use the 4-wire short to short the Hi/Lo and Sense
inputs.
Performance Test and Calibration
) is stable and between 18 °C and
cal
Note
Note
3

Test Considerations

3-5