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NI PXI-4110 Calibration Procedure
Adjusting Current Programming Accuracy
To adjust current programming, configure the external load using the
Equivalent Resistance
value for the iteration of channel
x
in Table 19, and then compare the current outputs measured
by an external DMM to the values in the
Output
column of Table 19. Refer to Figure 2 for the
necessary connections.
Note
The values in the
Output
(A) column are the settings for the current limit. This
column is labeled
Output
because the current limit is the value that the NI 4110
generates.
To ensure the system has had adequate time to settle, wait one second after requesting a new
voltage before taking a measurement with the DMM.
Use the niDCPower Cal Adjust Current Limit VI (
niDCPower_CalAdjustCurrentLimit
function) to calculate the new calibration coefficient values. Pass the current setpoints requested
by the NI 4110 to the Requested Outputs input of the VI, and pass the current values measured
by the DMM to the Measured Outputs input of the VI. Call this VI or function once per range.
Table 19.
NI 4110 Output Parameters for Current Programming
Accuracy Adjustment
Channel(s)
Current
Range
Iteration
Voltage
Setpoint (V)
Equivalent
Resistance (
Ω
)
Output
(A)
0
1 A
1
5
80
0.050
2
12
0.375
3
5
0.750
1
1 A
1
16
180
0.050
2
24
0.375
3
12
0.750
20 mA
1
9,600
0.001
2
900
0.010
3
480
0.020
2
1 A
1
-16
180
0.050
2
24
0.375
3
12
0.750
20 mA
1
9,600
0.001
2
900
0.010
3
480
0.020
