How neutral grounding adopted?

How neutral grounding adopted? 
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1 Answer

Answer :

For above 3.3 kV and below 22 kV resistance grounding is preferred. In this voltage level capacitive ground current is not large, so reactance grounding is not used. For below 3.3 kV that for 415 V external resistance earthing is not necessary. Because normal earthing (plate earthing) gives 1.5Ω resistance. This limits current to

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230/1.5=153A(Current limit without resistance).

For above 22 kV solid or direct grounding is used.

Reactance grounding is used where capacitive currents are large instead of resistance

grounding in transmission lines, generators etc. to neutralize capacitive current by

adding reactive current.  

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