Earthing switch is used for

 A. measuring of safety voltage

 B. protection of equipment from ground faults

 C. discharging residual energies

 D. all of the above


Answer: C. discharging residual energies


Explanation:

Isolator does not contain any arc quenching medium, it must be open under no load condition only. On the both side of the every equipment isolators are provided. For attending maintenance working on equipments these isolators are opened.

At the time of attending maintenance work, the earth switch is closed for discharging residual energies available in the equipment for the safety purpose.


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