NI 4070/4072 Calibration Procedure
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Note
NI recommends repeating the verification procedures after you perform these
adjustment procedures. Reverification ensures that the device you have calibrated is
operating within specifications after adjustments.
Caution
If you skip any of the steps within a section of the adjustment procedures,
NI-DMM does
not
allow you to store your new calibration coefficients. Instead, NI-DMM
restores the original coefficients to the EEPROM.
Setting Up the Test Equipment
If you have not already set up the test equipment, complete the following
steps:
1.
Remove all connections from the four input banana plug connectors on
the NI 4070/4072.
2.
Verify that the calibrator has been calibrated within the time limits
specified in the section, and that DC zeros calibration has been
performed within the last 30 days. Consult the Fluke 5700A/5720A
user documentation for instructions on calibrating these devices.
Note
Ensure that the calibrator is warmed up for at least 60 minutes before you begin this
procedure.
3.
Reset the calibrator.
4.
If you have not already done so, allow the NI 4070/4072 to warm up
for 60 minutes within a powered-on PXI chassis or PC.
Adjusting DC Voltage and Resistance
To adjust the DC voltage and resistance of the NI 4070/4072, complete the
following steps:
1.
Fasten the connectors on one end of the Fluke 5440 cable to the
appropriate banana plug connectors on the NI 4070/4072, and fasten
the connectors on the other end of the cable to the appropriate
calibrator binding posts. Figure 1 shows the correct connections.
Table 2 lists the cable connections.
2.
Wait two minutes for the thermal EMF to stabilize if the cable was not
previously connected in this configuration.
3.
Call
niDMM_InitExtCal
with the resource descriptor of the
NI 4070/4072 and your valid user password to output a calibration
session (
Cal Session
) that you can use to perform NI-DMM
calibration or regular measurement functions.
Note
You will use
Cal Session
in all subsequent function calls.