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NI PXIe-4480//4481 Calibration Procedure
3.
Create and configure an AI charge task on the device as shown in Table 11.
4.
Start the task.
5.
Acquire readings with the PXIe-4480.
6.
Calculate the RMS amplitude of the acquired fundamental harmonic. Compare this
amplitude to the appropriate charge limits in Table 10. The calculated amplitude is used to
verify the gain accuracy of the measured analog input channel at the 20,000 pC range
setting.
Table 10.
Charge Gain Accuracy Limits
Range
(pC)
Calibrator Output
As Found Test Limit
As Left Test Limit
Amplitude
(V
rms
)
Frequency
(Hz)
Lower
Limit
(pC
rms
)
Upper
Limit
(pC
rms
)
Lower
Limit
(pC
rms
)
Upper
Limit
(pC
rms
)
20,000
6.3
1,000
6.3 V *
C
CAL
*
0.9886
6.3 V *
C
CAL
*
1.0116
6.3 V *
C
CAL
*
0.995
6.3 V *
C
CAL
*
1.005
10,000
6.3
1,000
6.3 V *
C
CAL
*
0.9886
6.3 V *
C
CAL
*
1.0116
6.3 V *
C
CAL
*
0.995
6.3 V *
C
CAL
*
1.005
2,000
1.26
1,000
1.26 V *
C
CAL
*
0.9886
1.26 V *
C
CAL
*
1.0116
1.26 V *
C
CAL
*
0.995
1.26 V *
C
CAL
*
1.005
1,000
0.63
1,000
0.63 V *
C
CAL
*
0.9886
0.63 V *
C
CAL
*
1.0116
0.63 V *
C
CAL
*
0.995
0.63 V *
C
CAL
*
1.005
Table 11.
Charge Gain Accuracy Verification Configuration
Configuration
Value
Physical channel
Dev_name
/ai0
Measurement type
Charge
Range
20,000 (pC)
Acquisition mode
Finite number of samples
Sample rate
102,400
Samples per channel
102,400