Answer / vikramsenareddy

Ans: Transformer secondaty sholud have neutal point. This
we brought from earth. neutral point is earthed and
connected to T/F. for this we required one earh pit. and
for body earthing we should have another earh pit.
structure earthing for this another earth pit.

For an equipment we required only one earth pit for body
earthing and electrical accessories earthing( like
motors,switch gear, electronic instruments).

Answer / pk kar

There should be two distinct earth pit for TR neutral and
one for body earthing. This is as per IER. The earth
conductor crossection will depend upon the max fault
current that could flow in the system in case of a fault.
The thumb rule is, the crossecton of the earth conductor
should at least be half of one phase conductor.

Answer / farrukh

First of all we need to know ,Why we earth the transformer
neutral,? and the answer is that ,
Transformer has three out put phases and at any time all
these phases loads are not equal, so when the load is
unbalanced on any phase, the current may flow in neutral
line,and to dissolve the current at transformer end we need
to earth the neutral. Neutral pits are used to to provide
best conductive earth.

Answer / kartik

No of Earthing pits for a equipment depends upon components
of equipments prone to flow of fault current during
abnormal condition.Say for transformer, metal body &
neutral may carry fault current.So 2 nos pits for
transformer is required.

Answer / meka sekhar

normally, transformer body is conned to earth mat via earth
cables. No earth pit is required for body connection.
Normally Earth pit will be provided for neutral earthing
in order to facilitate isolation.

Answer / mrudang

earth pit is depnd upon

on vector group of transformer which we are used
equipment body earthing ,in delta connection we required
earthing transformer to protect from earthfault current

Answer / sathihsa

earth pits for tr depends on kva rating and fault current
use to carry.........

Answer / shvetang

the no of earth pits are depends upon the amount of earth
fault current that occurs during working of any equiment

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