Reference Accuracy Alignment - Fluke 9190A Operator's Manual

9190A
Operators Manual
4. Set the instrument conversion type for the UUT PRT input to resistance.
5. Let the readout stabilize for 20 seconds.
6. Take resistance measurements from the UUT PRT input at a 2-second interval. Take
7. Calculate the average of the measurements taken. Record these results.
8. Calculate the error with the formula below where actual is the calibrated resistance
9. Compare the error with the spec to determine the status. Record the result.

Reference Accuracy Alignment

The Reference Accuracy Alignment process calculates new offsets to be programmed
into the instrument for the reference probe input to correct for measured errors at specific
points over the resistance range of the input.
Perform the Reference Accuracy Alignment as follows:
1. Locate the results of the Reference Accuracy Tests.
2. Use the calculated errors and the previous (current) offset values and calculate the
3. Enter the new offset values into the instrument.
4. Let the readout stabilize for 70 seconds before a measurement is made.
5. Take As Left data for the Reference Accuracy Test, UUT PRT 4-wire Accuracy Test
4-20
a minimum of 40 samples.
value of the standard resistor. Record this result.
Error = Average – Actual
new offset values for each reference accuracy parameter with the formulas below:
REF1C0 = REF1C0
new previous
REF1C100 = REF1C100
new
error400 ohms)
and UUT 3-wire Accuracy Tests.
– error0 ohms
+ (0.625 x error0 ohms) – (0.5 x error100 ohms) – (0.125 x
previous