Refer to the following table as you complete the following steps.
Table 4.
Voltage Remote Sense Output Verification
Level
Range
Limit Range
and Limit
Test Point Load
1
Load
2
Voltage Remote Sense Test
Limit
Load
1
Load
2
1 mA
600 mV
0 mA
3 kΩ
3 kΩ
≤38.4 µV
≤6 µV
1 mA
1.
Set the niDCPower Output Function property or NIDCPOWER_OUTPUT_FUNCTION
attribute to DC Current for the NI 4138.
2.
Set the niDCPower Sense property or NIDCPOWER_ATTR_SENSE attribute to Remote.
3.
Make the necessary connections for this procedure, as shown in the following figure.
Figure 3.
Voltage Remote Sense Diagram, Part 1
2
NI-DCPower Device
Sense LO
Sense HI
HI
LO
Load1
4.
Set the first specified level range, limit range, and limit on the NI 4138.
5.
Measure the internal device temperature and perform self-calibration if necessary.
a)
If the internal device temperature exceeds T
cal
± 1 °C, wait up to 5 minutes for the
temperature to stabilize to within T
cal
± 1 °C.
b)
If after 5 minutes the stable temperature still exceeds T
cal
± 1 °C, call the self-
calibration VI or function.
6.
Set the level on the NI 4138 to the first specified test point.
7.
Take a voltage measurement using the NI 4138.
8.
Record the voltage from the previous step as
V1
.
9.
Repeat the previous three steps for the other test point specified in the range. This time,
record the value as
V2
.
10. Calculate the remote sense error using the following formula: Remote Sense Error = |V2 -
V1|. Record the value.
2
Follow industry best practices for minimizing thermal electromotive force (EMF) when making the
necessary connections for this procedure.
8
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NI PXIe-4138 Calibration Procedure