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NI PXIe-4480//4481 Calibration Procedure
Voltage Gain Accuracy Verification
Complete the following steps to verify the voltage gain accuracy:
1.
Using the equipment described in Table 1 (PXIe-4480) or Table 2 (PXIe-4481), connect the
module to the calibrator as shown in Figure 2 (six channels) or Figure 3 (analog input
channel 0).
2.
Configure the calibrator to generate an output with the amplitude and frequency listed in
the 10 V row of Table 5.
3.
Create and configure an AI voltage task on the device as shown in Table 6.
4.
If the coupling changes from DC to AC (for example, on the first gain verification point
tested), commit the configuration using the DAQmx Control Task VI and wait 5 seconds
for the input to settle. Subsequent gain verification points, which do not change the
coupling, do not require a delay.
5.
Start the task.
6.
Acquire readings with the PXIe-4480/4481.
Table 5.
Voltage Gain Accuracy Limits
Range
(V)
Calibrator Output
As Found Test Limit
As Left Test Limit
Amplitude
(V
rms
)
Frequency
(Hz)
Lower
Limit
(V
rms
)
Upper
Limit
(V
rms
)
Lower
Limit
(V
rms
)
Upper
Limit
(V
rms
)
10
6.3
1,000
6.2638
6.3364
6.29748
6.30252
5
3.15
1,000
3.1319
3.1682
3.14874
3.15126
1
0.63
1,000
0.62638
0.63364
0.62975
0.63025
0.5
0.315
1,000
0.31319
0.31682
0.31487
0.31513
Table 6.
Voltage Gain Accuracy Verification Configuration
Configuration
Value
Physical channel
Dev_name
/ai0 or
Dev_name
/ai0:5
Range
10 (V)
Coupling
AC
Terminal configuration
Pseudodifferential
Acquisition mode
Finite number of samples
Sample rate
102,400
Samples per channel
102,400