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NI PXIe-4339 Calibration Procedure
5.
Acquire a voltage measurement with the NI PXIe-4339.
a.
Create a DAQmx task.
b.
Create and configure the AI channels according to the values shown in Table 5.
c.
Start the task.
d.
Average the readings that you acquired, and record the values as
ch
x
_zero
, where
x
is the channel number.
e.
Clear the task.
f.
Set the calibrator to standby mode (STBY).
6.
Set the calibrator voltage output to 9 V.
7.
Set the calibrator to operate mode (OPR) to enable output.
8.
Acquire a voltage measurement with the NI PXIe-4339.
a.
Create a DAQmx task.
b.
Create and configure the AI channels according to the values shown in Table 5.
c.
Start the task.
d.
Average the readings that you acquired, and record the values as
ch
x
_9V
, where
x
is
the channel number.
e.
Clear the task.
f.
Set the calibrator to standby mode (STBY).
9.
Calculate the gain adjust (
Gadj
) and offset adjust (
Oadj
) of each channel using the
ch
x
_zero
and
ch
x
_9V
values recorded in the previous steps according to the following
equation:
Gadj_chx
= 9/(
chx_9V
-
chx_zero
)
Oadj_chx
=
chx_zero
Table 5.
AI Voltage Mode Setup
Configuration
Value
Channel Name
Dev1/ai0:7
Task
AI Voltage
Sample Mode
Finite number of samples
Sample Clock Rate
100
Samples Per Channel
100
Maximum Value
10
Minimum Value
-10
Units
Volts
