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National Instruments
9
NI PXIe-4353 Calibration Procedure
8.
Configure the timing properties for the voltage acquisition. Refer to Table 3.
9.
Start the acquisition.
10. Acquire the voltage data.
Note
Make sure that the calibrator and the NI PXIe-4353 are completely settled on the desired
resistance before acquiring data. When using the Fluke 5520A, wait at least 5000 ms for the system
to settle before issuing the start task function to the NI PXIe-4353.
11. Calculate the equivalent resistance using the following equation:
where
V
CJC_ave
is the average of the voltage values for the channel you acquired.
12. Compare the resulting average to the
Upper Limit
and
Lower Limit
values in Table 7. If the result
is between these values, the channel passes the test.
13. Clear the acquisition.
14. Repeat steps 5 through 12 for all CJC channels and test point values in Table 7. NI recommends
that you verify all values, although you can save time by verifying only the values used in your
application.
15. Close the DAQmx calibration session with the action Cancel.
16. Disable the calibrator output and disconnect the calibrator from the CAL-4353.
Note
After verifying your module, you can update the last calibration date by opening a DAQmx
external calibration session and closing it with the action Commit.
Table 3.
DAQmx Timing Function Rate and Samples per Channel for CJC Verification
Timing Mode
Rate (S/s)
Samples per Channel
1
17
10
2
34
10
3
68
20
4
90
35
5
90
50
6
90
80
7
90
150
R
CJC
40 k
Ω
2.048 V
V
CJC_ave
-------------------
1
–
----------------------------
=
