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National Instruments Corporation
47
NI PXI-4070 Calibration Procedure
Adjusting AC Voltage (AC- and DC-Coupled) Modes
Note
If you do not use the AC voltage modes for any measurements, or the accuracy of
these modes is irrelevant, you can skip this section in the calibration procedure and go
directly to the
section.
To adjust the AC voltage of the NI 4070, complete the following steps:
1.
Reset the calibrator.
Caution
Step 2 must be performed correctly to avoid shorting or electrical shock from
high voltage 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.
Refer to Table 8 for the appropriate calibrator output and parameter
values as you complete the following steps:
a.
On the calibrator, output the value listed under Calibrator Output
in Table 8 for the current iteration.
b.
Call
niDMM_CalAdjustGain
with
Mode
set to
NIDMM_VAL_AC_VOLTS
. Set the remaining parameters as shown
in Table 8 for the current iteration.
c.
Call
niDMM_CalAdjustGain
again, changing
Mode
to
NIDMM_VAL_AC_VOLTS_DCCOUPLED
.
4.
Repeat step 3 for each of the remaining iterations listed in Table 8.
Table 8.
niDMM_CalAdjustGain Parameters
Iteration
Calibrator Output
niDMM_CalAdjustGain Parameters
Amplitude
Frequency
Mode
Range
(V)
Input Resistance
Expected
Value
1
50 mV
1 kHz
NIDMM_VAL_AC_VOLTS
0.05
NIDMM_VAL_
1_MEGAOHM
0.05
50 mV
1 kHz
NIDMM_VAL_AC_VOLTS
_DCCOUPLED
0.05
NIDMM_VAL_
1_MEGAOHM
0.05
2
500 mV
1 kHz
NIDMM_VAL_AC_VOLTS
0.5
NIDMM_VAL_
1_MEGAOHM
0.5
500 mV
1 kHz
NIDMM_VAL_AC_VOLTS
_DCCOUPLED
0.5
NIDMM_VAL_
1_MEGAOHM
0.5