why earth hole size is biggest in plug point?
Answer Posted / rd dadhich
Who so ever are thinking of low resistance as cause of
bigger hole means bigger earth pin are forgeting the point
that the same earth current on fault is flowing through the
Phase pin and connecting wires , whose area is very less
compared to earth hole or Pin , are also carrying that
fault current and are suitably rated accordingly .
The correct reason is :-
1. While inserting equipment first get earth
connection.as pin goes first and so equipment is
earthed before supply is given
2.While withdrawing the plug the earth connection
disconnects in last. Power disnnect first and
earth in last
Reason of earth Pin larger in diameter than other pins in a
plug socket :-
Accidently also one can not inser earth pin in other
pins .
Both the above features are for foolfroop safety & no other
reason like low restance etc
Is This Answer Correct ? | 16 Yes | 3 No |
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