5.
Set the level on the PXIe-4135 to the first specified test point.
Complete the following 4 steps within 5 minutes or less of completing the previous step
in order to ensure the internal device temperature remains stable.
6.
Calculate the current through the shunt by completing the following steps.
a)
Take a voltage measurement across the shunt using the DMM.
b)
Divide the voltage measurement by the calibrated value of the shunt.
c)
Record the calculated value as
DMM Measured Current
.
7.
Calculate the lower and upper current measurement test limits using the following
formula:
Current Measurement Test Limits
=
DMM Measured Current
± (|
DMM Measured
Current
| *
% of Current
+
Offset
)
8.
Disconnect the DMM as shown in the following figure. Leave the PXIe-4135 output on.
Figure 7. Current Connection Diagram, Part 2
Triax Cable
Precision
Shunt
LO
LOS
HI
(T
riax)
HIS
(T
riax)
NI-DCPower Device
Sense LO
Sense HI
(Triax)
HI
(Triax)
LO
CHS GND
Shielded Combicon to
Banana/Bare wire
9.
Set the specified level range, limit range (part 2), and limit (part 2) on the PXIe-4135.
10. Take a current measurement using the PXIe-4135.
11. Record the value from the previous step.
12. Verify that the recorded PXIe-4135 value falls within the test limits.
13. Repeat steps 1-12 for each test point in the previous table.
Verifying 1 μA Current Measurement and Output
Compare a set of measured currents reported by the PXIe-4135 to the currents measured by a
DMM.
Complete this procedure only after successfully completing all previous verification
procedures. Verify level ranges in the order listed in the table.
Refer to the following table as you complete the following steps:
PXIe-4135 Calibration Procedure
|
© National Instruments Corporation
|
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