Earth Resistance Measurements
(1663 and 1664 FC)
The earth resistance test is a 3-wire test that has two test stakes and the earth
electrode under test. This test requires an accessory stake kit. Connect as
shown in Figure 12.
•
Best accuracy is achieved with the middle stake at 62 % of the distance to
the far stake. The stakes should be in a straight line and wires separated to
avoid mutual coupling.
•
Disconnect the earth electrode under test from the electrical system as you
do the test. Do not measure Earth resistance on a live system.
Figure 12. Earth Resistance Test Connection
62% L
L
Electrical Installation Tester
Measurements
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