Chapter 2
Using the SCXI-1530/1531
2-14
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b.
Select internal calibration as the calibration operation to
perform.
c.
Select the Default EEPROM load area as the area to update.
d.
The offset varies with the selected gain value. Therefore, enter the
high and low limits that correspond to the gain value for which
you are calibrating offset. See Table 2-1 for a list of the gain values
and the corresponding input limits you must enter.
3.
Run the application.
If you are using a C-based ADE, use the following procedure to do an offset
calibration on the SCXI-1530/1531:
1.
Make sure the DAQ device you are using has a valid calibration and
meets the accuracy specifications for your application.
2.
Use the NI-DAQ function
SCXI_Calibrate
to calibrate one channel
of the SCXI-1530/1531.
a.
Enter the DAQ device, DAQ channel, module slot, and module
channel for the channel you want to calibrate.
b.
Select internal calibration (0) as the operation to perform.
c.
Select the load area (1) as the EEPROM area to update.
d.
Since offset varies with gain, enter the gain setting for which you
are calibrating offset.
3.
Repeat step 2 for calibrating additional channels.
The SCXI-1530/1531 may take a few seconds to perform the calibration.
After completion, your module has new calibration constants stored for the
channels and gains calibrated.
Table 2-1.
Gain Values and Input Limits
Gain
High Limit
Low Limit
1
+10 V
–10 V
10
+1 V
–1 V
100
+0.1 V
–0.1 V