Table 7.
100 µA to 100 mA Current Output and Measurement Verification (Continued)
Level Range
Limit
Range and
Limit
Test Point
As-Found
Measurement Test
Limit (% of C
Offset)
As-Left Measurement
Test Limit (% of
C Offset)
1 mA
6 V
-1 mA
0.03% + 120 nA
0.013% + 15 nA
1 mA
10 mA
6 V
-10 mA
0.03% + 1.2 μA
0.013% + 150 nA
10 mA
100 mA
6 V
-100 mA
0.03% + 12 μA
0.013% + 1.5 μA
100 mA
1.
Make the necessary connections for this procedure, as shown in the following figure.
Figure 7.
Current Verification Connection Diagram
NI-DCPower Device
Sense LO
Sense HI
HI
LO
DMM
Current
Mode
+
–
2.
Set the niDCPower Output Function property or NIDCPOWER_OUTPUT_FUNCTION
attribute to DC Current for the NI 4138.
3.
Set the first specified level range, limit range, and limit on the NI 4138.
4.
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.
5.
Set the level on the NI 4138 to the first specified test point.
6.
Compare a DMM current measurement to the current measurement test limits.
a)
Take a current measurement using the DMM.
NI PXIe-4138 Calibration Procedure
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© National Instruments
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