Examples Of Use; Testing A Loop Connected To An Extended Earth - Chauvin Arnoux C.A 6410 Manual De Instrucciones

TESTING A LOOP CONNECTED TO AN EXTENDED EARTH

- In some countries (US, Northern Europe, ...) the electricity supply company brings
the live, negative and earth conductors to the final user. In order to get a good quality
for the earth present throughout the distribution network, an extended earth is
constituted from all the local earths in parallel: earths of electricity pylons, earths for
buildings, ...
- The railways are particularly protected from the risks of lightning or excess voltage.
The catenary carrying pylons, the rails and sometimes even the fencing is
connected to the earth. In addition, to get a very low value earth resistance, an
interconnection between pylons - rails - fencing is made thus creating a multiple
parallel earth.
- In order to protect lines from any disturbance, "FRANCE TELECOM" insulates the
cables by means of a conductive sheath regularly connected to the earth throughout
its length.
In the cases cited above, to rapidly check the efficiency of these multiple earths:
- successively insert the clamp around each conductor connected to the earth
- read the value attained in Ω on the display
- the resistance of the earth in question will be less than or equal to the value
measured in this way.

EXAMPLES OF USE

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