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buildings, etc.), They usually pass the overhead ground wire (cable shielding
layer) connected to form a grounding system.
As the Meter is in the above measurement, its equivalent electric circuit is
shown in the figure below:
Where: R
1
is the target grounding resistance.
R
0
is the equivalent resistance of the other entire tower grounding
resistances paralleled.
Although strictly on the theoretical grounding, because of the existence of
so-called "mutual resistance”, R
0
is not the usual parallel value in the sense of
electrical engineering (slightly higher than its IEC parallel output value). But
because a tower-grounding hemisphere was much smaller than the distance
between the towers, and with a great number of locations after all, R
0
is much
smaller than R
1
. Therefore, it can be justified to assume R
0
=0 from an
engineering perspective. In this way, the resistance we measured should be
R1.
Times of comparing tests in different environments and different
occasions with the traditional method proved that the above assumption is
entirely reasonable.
R
1
R
0
R
1
R
2
R
3
R
4
