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NI 9207 Calibration Procedure
Voltage Accuracy Verification
Complete the following procedure to determine the As-Found status of the NI 9207.
1.
Set the calibrator to Standby mode (STBY).
2.
Connect the NI 9207 to the calibrator as shown in Figure 1.
Figure 1.
Voltage Accuracy Connections
Note
If the calibrator outputs are truly floating, connect the negative output to a
quiet earth ground as well as COM to give the entire system a ground reference.
3.
Set the calibrator voltage to a Test Point value indicated in Table 4.
4.
Set the calibrator to Operate mode (OPR).
5.
Acquire and average samples.
a.
Create and configure an AI voltage task on the NI 9207 according to Table 2.
b.
Configure the AI voltage task according toTable 3.Set the ADC timing mode to
high-resolution.
c.
Start the task.
d.
Average the readings.
e.
Clear the task.
1
Connections when using a calibrator with a guard connection.
2
Connections when using a calibrator with no guard connection.
Table 2.
NI 9207 Configuration for Voltage Accuracy Verification
Input Range
Scaled Units
Terminal Configuration
Min
Max
-10
10
Volts
Differential
Table 3.
NI 9207 Voltage Timing Configuration
ADC Timing Mode
Sample Mode
Samples to Read
High-Resolution
N Samples
5
High-Speed
N Samples
75
NI 9207
C
a
li
b
r
a
tor
AI
x
–
AI
x
+
COM
HI
LO
G
ua
rd
NI 9207
C
a
li
b
r
a
tor
AI
x
–
AI
x
+
HI
LO
1
2
