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resistance value by connecting the test lines with both ends.
So, if the measurement value of the Meter is smaller than the allowable
value of the grounding resistance, then the two grounding bodies are qualified
for grounding resistance.
(2) Three-Point Method
As shown in the figure below, in the vicinity of the measured grounding
body R
A,
find two independent grounding bodies of better grounding state R
B
and R
C.
First, link R
A
and R
B
with a test line; use the Meter to get the first reading
R
1
.
Second, have RB and RC linked up, as shown in the following figure. Use
the Meter to get the second reading R2.
Third, have RC and RA linked up, as shown in the following figure. Use
the Meter to get the third reading R3.
R
B
R
A
R
1
R
C
R
A
R
B
R
3
R
C
R
B
R
A
R
2
R
C
