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NI TB-9214 Calibration Procedure
c.
Start the task.
d.
Average the readings and record the value as CJC
temp0
.
e.
Clear the task.
8.
Set the thermocouple calibrator output to CJC
temp0
.
This ensures that during the
thermocouple measurements, the input channel measures very close to 0 V, which
eliminates gain errors in the NI 9214.
9.
Acquire and average samples.
a.
Create and configure an AI temperature thermocouple channel for the NI 9214
according to Table 4.
b.
Configure the AI temperature thermocouple channel timing according to Table 5.
c.
Disable open thermocouple detection on the NI 9214.
d.
Start the task.
Note
•
Make sure the thermocouple calibrator and NI 9214 are completely settled at the
desired temperature setting before acquiring data.
•
Wait at least 300 ms for the Ectron 1140A to settle before acquiring data with the
NI 9214.
•
Disregard the first six seconds of the acquisition to compensate for the open
thermocouple settling time of the NI 9214.
e.
Average the readings for each channel. Record the average of the readings for each as
Temp
ai
x
where
x
is the channel number.
f.
Clear the task.
10. Perform the following calculation using the recorded Temp
ai
x
and CJC
temp0
values.
Temp
aix
- CJC
temp0
= Temp
ErrorCh0
11. Compare the calculation result for each channel to the Upper Limit and Lower Limit values
in Table 6.
12. Remove the NI TB-9214 from the NI 9214.
Table 4.
NI 9214 Thermocouple Channel Configuration
Physical
Channels
Minimum
Value
Maximum
Vale
Units
Thermocouple
Type
Autozero
ai0:15
0
100
°C
E
Every Sample
Table 5.
NI 9214 Thermocouple Timing Configuration
Timing
Mode
Sample
Mode
Samples Per
Channel
Rate (S/s)
High Resolution
Finite
36
1
