Earth Resistance Measurement (four-wire method)
• To perform this measurement the user requires the Amprobe Earth Measurement Set
The four-wire measurement is applied instead of the three-wire measurement when dealing
with extremely low earth resistances and if the resistance of test lead between instrument
and earth connector interfere the measurement result.
Here, the earth to be measured is connected via the connectors E and ES, the measurement
selection switch is set to "4pol" and a measurement are performed as described.
H
S
ES
E
Figure 6: four-wire measurement
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