TENTECH EM4058, Руководство пользователя

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6.3. Observations about grounding diffusion
systems (GDS)
In order to obtain a valid result when measuring a grounding diffusion
system (GDS), some additional prerequisites must be observed: the
current electrode must be away enough from the GDS to prevent their
influence areas from overlapping, while the voltage rod (probe) must be
set up in the potential plateau area. Usually, the radius of each influence
area is about three to five times bigger than the electrode’s dimensions.
The appropriate compliance of this condition must be checked by carrying
out three successive measurements of the GDS resistance, keeping the
current rod in position, but moving the voltage rod about 2 meters
between measurements (
L , M , and N points in the image below). If all
three measurements show the same result (within the earth meter
specified error margins) the measurement should be considered correct.
Otherwise, the distance from the current rod to the GDS should be
significantly increased and the process, repeated.
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