©
National Instruments Corporation
29
NI PXI-4070 Calibration Procedure
You have completed verifying the 4-wire resistance of the NI 4070. Select
one of the following options:
• If you want to continue verifying other modes, go to the
•
If you do not want to verify other modes and you are performing a
post-adjustment verification, go to the
section.
•
If you do not want to verify any additional modes and you are
performing a pre-adjustment verification, call
niDMM_close
to close
the session.
Verifying 2-Wire Resistance
To verify the 2-wire resistance of the NI 4070, complete the following
steps:
1.
Reset the calibrator.
Caution
Step 2 must be performed correctly to avoid shorting on unconnected spade lugs.
2.
Connect the calibration cable assembly with the connector block
plugged into the NI 4070 and with the spade lugs connected to the
appropriate binding posts on the calibrator, as described in Figure 3
and Table 1.
3.
Wait two minutes for the thermal EMF to stabilize if the calibration
cable assembly was not used previously in this configuration.
4.
Output 0
Ω
on the calibrator with 2-wire compensation turned on, but
with external sense turned off.
5.
Call
niDMM_reset
to reset the NI 4070 to a known state.
6.
Call
niDMM_ConfigureMeasurement
with the following
parameters:
•
Function
=
NIDMM_VAL_2_WIRE_RES
•
Range
=
100e6
•
Resolution
=
100
7.
Call
niDMM_Read
and store the result as the 100 M
Ω
range offset.
8.
Call
niDMM_ConfigureMeasurement
with the following
parameters:
•
Function
=
NIDMM_VAL_2_WIRE_RES
•
Range
=
10e6
•
Resolution
=
10
9.
Call
niDMM_Read
and store the result as the 10 M
Ω
range offset.
