Calibration Adjustment - Fluke 287 Calibration Manual

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Calibration Manual
Step
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[1] Must allow for source and Meter settling before recording reading.
[2] When using the relative mode (REL ) to compensate for offsets.
[3] The Meter accuracy is not specified at this frequency with Low-pass filter on. The display reading limits shown in table 4, checks
that the Low-pass filter is active and follows an expected roll-off curve.
[4] With a film capacitor or better, using relative mode (REL ) to zero residual.
[5] Test limits are mathematically guard banded to ensure performance, at 20 kHz and lower.
[6] To obtain full accuracy in DC mV, Temperature, ohms, and Lo , let the Meter stabilize for 20 minutes after using LoZ.
[7] To avoid calibrator overload/current limit condition, step the calibrator output to 60 V and then 120 V.

Calibration Adjustment

The Meter features closed-case calibration adjustment using known reference sources.
The Meter measures the applied reference source, calculates correction factors and stores
the correction factors in nonvolatile memory.
The following sections present the features and Meter pushbutton functions that can be
used during the Calibration Adjustment Procedure.
Before you begin the adjustment procedure, the Meter must be allowed to reach the
ambient temperature of the lab environment. Depending on temperature gradient, this
could take up to several hours.
Perform the Calibration Adjustment Procedure should the Meter fail any performance test
steps listed in Table 4.
20
Table 4. 287/289 Performance Test Steps (cont.)
Function Range
A DC 5000.0 A
mA AC 50.000 mA
mA AC 50.000 mA
mA AC 400.00 mA
mA AC 400.00 mA
mA DC 50.000 mA
mA DC 50.000 mA
mA DC 400.00 mA
Connect 5520A, Auxiliary 20A output, to Meter's A and COM Input Terminals
AAC 5.0000 A
AAC 10.000 A
ADC 5.0000 A
ADC 10.000 A
Connect 5520A Normal Output to Meter's V Input Terminal
[6]
LoZ (289) 1000 V
Frequency
Input Level
or Model
5000 A
4 mA 20 Hz
30 mA 30 kHz
300 mA 30 kHz
400 mA 60 Hz
0.1 mA
50 mA
400 mA
5 A 1 kHz
5 A 1 kHz
5 A
10 A
[7]
120 V 60 Hz
[1]
Display Reading
Lower Upper
Limit Limit
4996.0 5004.0
3.940 4.060
[5] [5]
29.375 30.625
284.60 315.40
397.55 402.45
0.090 0.110
49.965 50.035
399.38 400.62
4.9580 5.0420
4.955 5.045
4.9840 5.0160
9.968 10.032
113.6 126.4