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NI PXI-4130 Calibration Procedure
Adjusting Current Programming Accuracy
Connect the NI 4130 channel
x
to the DMM or to the Fluke 5700A/5720A/5730A calibrator, as
illustrated in Figure 3 or Figure 4. Configure the DMM to the mode and range listed for
the corresponding channel and range in Table 4. When applicable, configure the
Fluke 5700A/5720A/5730A calibrator to the
Resistance
value for the corresponding channel
and range in Table 4. Enable external sense (4-wire mode) on the calibrator. Record the
resistance value displayed by the calibrator.
The setup in Figure 3 is used for the 200
μ
A, 2 mA, 20 mA, and 200 mA current ranges of
channel 1. The setup in Figure 4 is used for the 1 A current range of channel 0 and the 2 A
current range of channel 1.
To ensure the system has had adequate time to settle, wait one second after requesting a new set
of parameters before taking a measurement with the DMM. Set the Overranging Enabled
property of the NI 4130 to
True
.
For the 200
μ
A, 2 mA, 20 mA, and 200 mA current ranges of channel 1, divide the voltage
measurement you recorded with the DMM by the resistance measurement you recorded from the
calibrator to calculate the output current. For the 1 A current range of channel 0 and the
2 A current range of channel 1, the DMM measures the output current directly. Subtract the
Output
value for the iteration of channel
x
in Table 20 from the output current calculated above
to obtain the output error.
Pass the requested current setpoints and measured current values to the niDCPower Cal Adjust
Current Limit VI (
niDCPower_CalAdjustCurrentLimit
function) to calculate the new
calibration coefficient values. Each current limit range requires a unique call to the
niDCPower Cal Adjust Current Level VI. For channel 1, each current limit range has one set of
iterations with a positive voltage level and another set with a negative voltage level. Within the
same current limit range, outputs related to the positive voltage level and outputs related to the
negative voltage level require unique calls to the niDCPower Cal Adjust Current Level VI.
Refer to the Output column of Table 20 for the current limit for each iteration.
After applying a new set of configurations to the NI 4130, wait 3 seconds before taking a new
measurement with the DMM or the NI 4130.