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NI 449
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Calibration Procedure
If verifying an NI 4492/4497/4499, repeat steps 2 through 8 for each gain setting that your
device supports. Refer to Table 10 for the gain settings supported by NI 449x devices. For
each gain setting, including 0 dB, separately verify at sample rates of 102.4 kS/s and
204.8 kS/s. In step 2, change the output of the calibrator based on the gain setting that is
being verified. Table 8 lists the amplitude and frequency to use for each gain setting. When
performing step 3, adjust the gain and sample rate parameters appropriately.
10. Repeat steps 1 through 9 for all analog input channels on the device. Connect the output of
the calibrator to the channel being verified during step 1. In step 3, replace
ai0
in the
physical channel parameter with the channel being verified.
AI Flatness Verification
Complete the following steps to verify the AI flatness:
1.
Connect the output of the calibrator to channel AI 0 on the device.
2.
If verifying an NI 4495/4496/4498, configure the calibrator to generate a tone with the
amplitude and frequency listed in the 0 dB gain row of Table 7. Wait 5 seconds for the
inputs to settle.
If verifying an NI 4492/4497/4499, configure the calibrator to generate a tone with the
amplitude and frequency listed in the 0 dB gain row of Table 8. Wait 5 seconds for the
inputs to settle.
3.
Create and configure an AI voltage task on the NI 449x as shown in Table 11.
Table 10.
NI 4492/4496/4497/4498/4499
Supported Gain Settings
Device
Gain Settings
NI 4492
0 dB, 20 dB
NI 4496
NI 4497
NI 4498
0 dB, 10 dB, 20 dB, 30 dB
NI 4499
Table 11.
NI 449x AI Flatness Verification Configuration
Configuration
Value
Minimum value
–10.0
Maximum value
10.0
Terminal configuration
Pseudodifferential
Acquisition mode
Finite number of samples
Rate
204,800.0
