Measurement Method Of Earth Resistance; Multi-Point Grounding System - ETCR ETCR2000+ Manual

VIII. Measurement Method of Earth Resistance

1. Multi-Point Grounding System

As for the multi-point grounding system (such as electricity
transmission
communications systems, certain 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 is the target grounding resistance.
1
R is the equivalent resistance of the other entire tower
0
grounding resistances paralleled.
Although strictly on the theoretical grounding, because of the
existence of so-called "mutual resistance", R
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
smaller than R
an engineering perspective. In this way, the resistance we
tower grounding
. Therefore, it can be justified to assume R
1
system,
-19-
grounding
is not the usual
0
is much
0
=0 from
0
cable