Two-point gain and offset calibration, Two-point gain and offset calibration -32 – National Instruments Module SCXI-1125 User Manual
Page 69
Chapter 5 Using the SCXI-1125
5-32
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If you are using a C-based ADE, use the following procedure to do an offset
calibration on the SCXI-1125:
1.
Make sure the DAQ device or DMM 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-1125.
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 you are going to
perform.
c.
Select the load area (1) as the EEPROM area you want to update.
d.
Since offset varies with gain, enter the gain setting for which you
are calibrating offset.
e.
Enter
1
for the terminal block gain since it is not used.
f.
Enter
0.0
as the input reference voltage.
3.
Repeat step 2 for calibrating additional channels.
The SCXI-1125 may take a few seconds to perform the calibration. After
completion, your module will have new calibration constants stored for the
channels and gains you calibrated.
Two-Point Gain and Offset Calibration
If you also need to calibrate the gain constants on the SCXI-1125, you must
use an external reference to perform a two-point calibration. Please refer to
the SCXI-1125 Calibration Procedures document for more information on
doing an external two-point gain and offset calibration.
1000
0.005 V
2000
0.0025 V
Table 5-9. Gain Values and Input Limits (Continued)
Gain
Range (±)