National Instruments PXIe-5172, Процедура калибровки, Страница: 20 / 38

• Sample rate: 125 MS/s
• Minimum number of points: 1,048,576 samples
4. Configure the function generator and generate a waveform with the following
characteristics:
•
Waveform: Sine wave
• Amplitude: the Test Point value from the AC Amplitude Accuracy Verification table
• Frequency: 50 kHz
• Load impedance: the Input Impedance value from the AC Amplitude Accuracy
Verification table
Note These values assume you are using a NI 5402/5406 function generator.
For other function generators, the output voltage varies with load output
impedance, up to doubling the voltage for a high impedance load.
5. Wait 0.1 second for the output of the function generator to settle.
6. Acquire and measure the amplitude of the sine wave using the PXIe-5172 and the Extract
Single Tone Information VI. Convert the result from V
pk
to V
rms
. Record the result as
V
PXIe-5172 Measured
.
7. Measure the amplitude of the sine wave in V
rms
using the DMM. Record the result as
V
DMM Measured
.
8. Calculate the amplitude error using the following formula:
AC Voltage Error = 20 × log
10
( V
PXIe-5172 Measured
/ V
DMM Measured
)
9. Compare the amplitude error to the appropriate Limit from the AC Amplitude Accuracy
Verification table.
10. Repeat steps 2 through 9 for each configuration listed in the AC Amplitude Accuracy
Verification table.
11. Disable the function generator output.
12. Connect the DMM and function generator to channel 1 of the PXIe-5172 as shown in the
AC Verification Test Connections figure and repeat steps 2 through 9 for each
configuration listed in the AC Amplitude Accuracy Verification table.
13. Disable the function generator output.
14. Connect the DMM and function generator to channel 2 of the PXIe-5172 as shown in the
AC Verification Test Connections figure and repeat steps 2 through 9 for each
configuration listed in the AC Amplitude Accuracy Verification table.
15. Disable the function generator output.
16. Connect the DMM and function generator to channel 3 of the PXIe-5172 as shown in the
AC Verification Test Connections figure and repeat steps 2 through 9 for each
configuration listed in the AC Amplitude Accuracy Verification table.
17. Disable the function generator output.
Note If you are verifying the PXIe-5172 (8CH), proceed to the next step. If
you are verifying the PXIe-5172 (4CH), AC Amplitude Verification is
complete.
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