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ni.com
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NI 9219 Calibration Procedure
k.
Call and configure the NI 9219 adjustment function according to Table 37.
l.
Repeat steps e through k for every value in the array.
m. Close the calibration session.
3.
Repeat step 2 for each 4-wire resistance mode on the NI 9219.
4.
Disconnect the DMM and the resistor from the device.
5.
Repeat steps 1 through 4 for each channel on the NI 9219.
4-Wire RTD, 3-Wire RTD, and Quarter-Bridge Accuracy
Adjustment
Complete the following steps to adjust the 4-wire RTD accuracy, 3-wire RTD accuracy, and
quarter-bridge accuracy of the NI 9219.
1.
Connect the NI 9219 to the resistor and the DMM as shown in Figure 7. Connect the sense
leads of the DMM as close as possible to the same point that the sense leads of the NI 9219
(HI and LO) connect to the resistor to ensure that the DMM reference measurements
include the same lead wire resistance as the NI 9219 4-wire measurements.
2.
Adjust the NI 9219 4-Wire RTD, 3-Wire RTD, and Quarter-Bridge accuracy.
a.
Initialize a calibration session on the NI 9219. The default password is
NI
.
b.
Call and configure the NI 9219 setup calibration function, to place the channel in RTD
mode, according to Table 41.
c.
Input the external temperature in degrees Celsius.
d.
Call the NI 9219 get C Series adjustment points function to obtain an array of
recommended calibration currents for the NI 9219.
Table 43.
Setup for 4-Wire and 2-Wire Accuracy Adjustment (Configuration 3)
Min (
Ω
)
Max (
Ω
)
Physical
Channels
Measurement
Type
Bridge
Configuration
0
1050
cDAQMod8/ai
x
Resistance
No Bridge
10500
Table 44.
Adjustment Configuration
Physical Channel
Reference Value
cDAQMod8/ai
x
The DMM reading
Table 45.
Setup Configuration for RTD Accuracy Adjustment (Configuration 1)
Min (
Ω
)
Max (
Ω
)
Physical
Channels
Measurement
Type
Bridge
Configuration
1050
10500
cDAQMod8/ai
x
Resistance
No Bridge