Fluke Calibration 5322A - Select the Residual Impedance Correction Mode

Multifunction Electrical Tester Calibrator
Use the Loop and Line Impedance Function
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Note
During a loop residual impedance test, internal test current flowing
between the L and N mains wires is approximately 4 A. Both line and
loop residual impedance tests can be performed on a protected
network.
Select the Residual Impedance Correction Mode
To make accurate line and loop impedance calibrations, the actual line and loop
impedance of the power mains connection of the Calibration must be taken into
consideration. To do this, the Product uses one of three methods to compensate
for the residual impedance present at the power inlet. Two methods are available
with the standard instrument, and a third method is available with the optional
5322A/VLC configuration.
When doing these tests, the displayed resistance value is the sum of the
selected resistance plus any line or loop compensation. Without compensation,
only the selected resistance is displayed. The first method (MAN) is a manual
correction of the residual impedance. The residual impedance can be added to
the calibration value manually. The displayed value is the sum of the selected
resistance and the manually entered value. The second method (SCAN) uses an
internal circuit that scans the residual impedance, saves the value, and then
adds it to the selected resistance value. The displayed value is the sum of the
selected resistance and the value determined by the scanning process.
A third method, COMP (5322A/VLC only) uses an internal electronic
compensation circuit to effectively eliminate the actual residual impedance in the
power mains circuits of the Product from the impedance measured by the DUT.
In this way the DUT measures just the selected Calibrator resistance value. This
compensation circuit is limited to 25 A peak of DUT current. If these values are
exceeded, the compensation block is disconnected and the compensation mode
set to OFF. The maximum impedance compensation depends on the load
current, typically 2 Ω at low-level testing.
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