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NI 4071 7½-Digit FlexDMM Calibration Procedure
Appendix A: Calibration Options
The complete calibration process consists of verifying, adjusting, and reverifying a device.
During verification, you compare the measured performance to an external standard of known
measurement uncertainty to confirm that the product meets or exceeds specifications. Figure 7
shows the procedural flow for verification. During adjustment, you correct the measurement
error of the device by adjusting the calibration constants and storing the new calibration
constants in the EEPROM. Figure 8 shows the procedural flow for adjustment.
Normally, the calibration sequence is as follows:
1.
Verify the NI 4071 using the 2-year accuracy limits (or the 90-day accuracy limits if it has
been externally calibrated within that time).
2.
Adjust the NI 4071.
3.
Reverify the NI 4071 using the 24-hour accuracy limits (or the 2-year accuracy limits when
the 24-hour limits are not specified).
Note
You must compare the verification limits provided in this procedure with the
most recent specifications. Refer to the latest NI 4071 specifications at
ni.com/
manuals
.
Depending on your measurement and accuracy requirements, a complete calibration of the
NI 4071 may not be necessary. A number of options are available that can shorten the calibration
time. The following options are available:
•
Complete calibration—Performing the entire calibration procedure from beginning to end;
guarantees that the NI 4071 performs within the published specifications for all modes and
ranges
•
Complete calibration with exceptions:
–
Omitting AC voltage mode steps if you do not use the AC voltage modes or if the AC
voltage accuracy is irrelevant
–
Omitting DC/AC current mode steps if you do not use the current modes or if the
DC/AC current accuracy is irrelevant
–
Omitting both AC voltage and DC/AC current mode steps if you do not use those
modes or if the accuracy of those measurements is irrelevant
