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How would we calculate the no of earthing pits required
for motor /panel
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Answer Posted / babloo
the no.of earth pits is usually calculated considering the
fault current, for suppose if the short ckt occurs b/w the
2 phases the fault current will be 3times to the normal
current. For example A 55KW motor carrying the current of
80A during normal running , when the short ckt occurs the
fault current has to dissipate through the earth, so the
earth must be around 25 X 3mm strip.
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