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National Instruments Corporation
41
NI PXI-4070 Calibration Procedure
Adjusting DC Voltage and Resistance
To adjust the DC voltage and resistance of the NI 4070, complete the
following steps:
Caution
Step 1 must be performed correctly to avoid shorting on unconnected spade lugs.
1.
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.
2.
Wait two minutes for the thermal EMF to stabilize if the calibration
cable assembly was not previously connected in this configuration.
3.
Call
niDMM_InitExtCal
with the resource descriptor of the NI 4070
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.
Note
The default user password for adjusting the NI 4070 is
NI
.
4.
Call
niDMM_ConfigurePowerLineFrequency
with
PowerLine
Frequency
set to
50
or
60
, depending on the power line frequency
(in Hz) that your instruments are powered from; select
50
for 400 Hz
power line frequencies
5.
Output 100 mV on the calibrator with the range locked to 2.2 V.
6.
Call
niDMM_CalAdjustGain
with the following parameters:
•
Mode
=
NIDMM_VAL_DC_VOLTS
•
Range
=
0.1
•
Input Resistance
=
NIDMM_VAL_10_MEGAOHM
•
Expected Measurement
=
0.1
7.
Output –100 mV on the calibrator with the range locked to 2.2 V.
8.
Call
niDMM_CalAdjustGain
with the following parameters:
•
Mode
=
NIDMM_VAL_DC_VOLTS
•
Range
=
0.1
•
Input Resistance
=
NIDMM_VAL_10_MEGAOHM
•
Expected Measurement
=
–0.1
9.
Output 10 V on the calibrator.