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NI 9144 User Guide and Specifications
The default scan list is defined as shown in Table 38.
NI 9214 Calibration Data
Calibration data is set up by the driver during initialization. The calibration conversion is
performed on the module ADC itself. The third-party user does not need to check the index
0x2100 to calibrate the data manually.
Use the following equation to calculate raw voltage for the cold-junction compensation (CJC):
where
V
CJCvoltage
represents raw CJC voltage
Bit
CJC
represents binary bits for the CJC
Use the following equation to calculate raw voltage for the thermocouple (TC):
where
V
TCvoltage
represents raw TC voltage
Bit
TC
represents binary bits for the TC
After calculating the CJC and the TC voltage, use the
NI 9214 Getting Started.lvproj
located by default in the
LabVIEW\examples\CompactRIO\Module Specific
directory
to calculate the resistance of the thermistor and the CJC temperature in degrees Celsius.
Table 38.
NI 9214 Vendor Configuration Extensions
Index
Sub
Type
Value
0x2001
0
ARR:U32
21
1
20
2
0
3
1
…
—
20
18
21
19
V
CJCvoltage
78.125
mV
78.125
mV
+
(
)
2
24
-------------------------------------------------------------
Bit
CJC
×
=
V
TCvoltage
78.125
mV
78.125
mV
+
(
)
2
24
-------------------------------------------------------------
Bit
TC
×
=