National Instruments NI PXIe-4464, Calibration Procedure

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NI PXIe-4464 Calibration Procedure | © National Instruments | 11
6. Calculate the RMS amplitude of the acquired fundamental harmonic. The measured
amplitude represents V
1kHz
referenced in Table 9.
As an example, you can use the Extract Single Tone Information VI to help calculate RMS.
Note that the output of this VI is peak amplitude, and you must divide the result by
√ 2 to
convert to RMS.
7. Stop and clear the task.
8. Repeat steps 2 through 7 for each row in Table 9. When performing step 2, instead of
1 kHz, configure the calibrator output to the frequency listed in Table 9. The calibrator
output amplitude remains constant. Compare this amplitude to the appropriate limits in
Table 9.
Note
The value of V
1kHz
is the measured amplitude of the 1 kHz tone, not the
nominal amplitude listed in Table 7.
9. Repeat steps 2 through 8 for each gain setting of the device. When performing step 2,
configure the calibrator output to the amplitude and frequency indicated for the gain range
to be verified. When performing step 3, set the
gain
1
parameter to -10, 0, 10, 20, and 30 as
required.
10. Repeat steps 1 through 9 for all input channels of the device. In step 1, connect the output
of the calibrator to the channel being verified. In step 3, replace
ai0
in the
physical
channel
parameter with the channel being verified.
1 Refer to Table 3 for the maximum and minimum voltages to specify to ensure the specified gain range is
used on the module.
Table 9.
AI Flatness Limits
Calibrator Output
Frequency (Hz)
Test Limit
(-10 dB, -20 dB ranges)
Test Limit
(0 dB, 10 dB, 20 dB, 30 dB
ranges)
Min Max Min Max
40 0.97724 * V
1kHz
1.02329 * V
1kHz
0.99931 * V
1kHz
1.00069 * V
1kHz
20000 0.97724 * V
1kHz
1.02329 * V
1kHz
0.99931 * V
1kHz
1.00069 * V
1kHz
45000 0.93325 * V
1kHz
1.07152 * V
1kHz
0.99655 * V
1kHz
1.00346 * V
1kHz
92200 0.89125 * V
1kHz
1.12202 * V
1kHz
0.98855 * V
1kHz
1.01158 * V
1kHz