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connecting the end of the test lead to the end.
Therefore, if the measured value of the clamp meter is less than
the allowable value of the grounding resistance, then the
grounding resistances of the two grounding bodies are qualified.
⑵
. Three Point Method
As shown in the figure below, find two independent grounding
bodies RB and RC near the measured grounding body RA.
The first step is to connect RA and RB with a test lead, see the
picture below. Read the first data R1 with a clamp meter.
The second step is to connect RB and RC, as shown in the
figure below. Use the clamp meter to read the second data R2.
The third step is to connect RC and RA, as shown in the
