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NI PXIe-4339 Calibration Procedure
5.
For each value in Table 4, repeat steps 3 through 4 for all channels.
6.
Set the calibrator to standby mode (STBY).
7.
Disconnect the calibrator from the terminal block.
Ratio Mode Accuracy Verification
Ratio mode verification uses paired channels in voltage mode to measure the excitation voltage
of the ratio mode channel that is being verified. The paired channels are connected via internal
circuitry on the NI PXIe-4339. The channel pairs are CH0 and CH1, CH2 and CH3, CH4 and
CH5, and CH6 and CH7.
To verify ratio mode accuracy, you will acquire a voltage measurement (
Vmeas
) for each paired
channel at 0 V and 9 V outputs. From these results, you can determine the ratio verification
adjustment factors, including the gain adjust (
Gadj
) and offset adjust (
Oadj
) values. The ratio
verification adjustment factors are then used to calculate the voltage adjustment (
Vadj
) value
for the paired channel.
-0.1
0.1
0.095
0.094869
0.095131
-0.2
0.2
-0.19
-0.190203
-0.189797
-0.2
0.2
0
-0.000089
0.000089
-0.2
0.2
0.19
0.189797
0.190203
-0.5
0.5
-0.475
-0.475418
-0.474582
-0.5
0.5
0
-0.000133
0.000133
-0.5
0.5
0.475
0.474582
0.475418
-10
10
-9.5
-9.507261
-9.492739
-10
10
0
-0.001561
0.001561
-10
10
9.5
9.492739
9.507261
Table 4.
Voltage Mode Accuracy Limits (Continued)
Range (V)
Test Point (V)
Lower Limit (V)
Upper Limit (V)
Minimum
Maximum
