How many earthpit needed to generator??

If we have 30kva, 250 kva, 300kva d.g set than how many earthing we do? 
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2 Answers

Answer :

According to Indian Std. DG Set Should have four Earthing 

Pits Each Should have Separate Copper Plate Accoring to Std.

-Run two properly sized Copper or GI Earthing Conductors 

from the Neutral Bushing/Terminal of the DG Set's 

Alternator and connect one each to the two neutral earth 

pits. Similarly, the alternator will have two earthing 

terminal on its body (at diagonally opposite ends); Run two 

properly sized Copper or GI Earthing Conductors from these 

body earthing terminals of the DG Set's Alternator and 

connect one each to the two body earth pits. But, you MUST 

inter-connect all these four (two neutral and the two body) 

earth pits by properly sized Copper or GI Earthing 

Conductor.
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Answer :

We should have two distinct earthing for neautral earthing and two for Body earthing.To achieve minimal resistance neautral earthpit should be connected in parallel.similarly body earthing too.
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