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NI 9219 Calibration Procedure
Note
The test limits listed in Tables 4 are derived using the values in Table 53.
9.
Set the source output to zero.
10. Repeat steps 2 through 9 for all test points on the NI 9219.
11. Repeat steps 2 through 10 for all channels on the NI 9219.
12. Disconnect the source and the DMM from the device.
Thermocouple Accuracy Verification
Complete the following steps to verify the thermocouple accuracy of an NI 9219.
1.
Connect the NI 9219 to the DMM and source as shown in Figure 2.
Figure 2.
Thermocouple Accuracy Verification Connections to the NI 9219
2.
Set the source to the appropriate test point value indicated in Table 7. Use the smallest
available range needed to source each test point. Using a range larger than necessary creates
unwanted additional noise.
3.
Configure the DMM for a voltage measurement in the lowest appropriate range according
to the test point from Table 7.
4.
Enable Auto Zero on the DMM.
5.
Acquire a voltage reading with the DMM. Record the measurement as V
ref
.
6.
Acquire and average samples.
a.
Create an AI thermocouple task on the NI 9219 according to Table 5.
V+
V–
HI
V
LO
NI 9219
DMM
S
ource
HI (4)
LO (5)
Ch 0
HI (4)
LO (5)
Ch 1
HI (4)
LO (5)
Ch 2
HI (4)
LO (5)
Ch 3