Answer / krishna r

if there any short occur, the heavy current will pass
through in that top point. its size is large because it
should be low resistance, according to resistivity = RA/L,
ie, Area is inversely proportional to resistance. so if area
increases , resistance decreases.......... please reply if
you find answer wrong .....

Answer / k.prakashchandra

The topmost hole is for earthing and it is connected to the
body of the equipment.In case of severest earth fault ,the
fault current may go upto 25 A ( depending on earth
resistances of both Tr neutral and earth wire) and hence the
size of the pin is larger.Further the top can be fixed in
one position only so that neutral and phase wires are not
interchanged.And also ,with the third larger pin the top
stays firm in position.The pins are slitted so that they
remain inside the holes tightly pressed.

Answer / shahid

If there is any fault like ground. and we connect the plug
into socket , first will connect top point. and fault
current flow through top point.Not follow any other route.
Also we will save from sock.
This is only for safe use.

Answer / aayush shrivastava

if we apply the power in any conductor,their is some charges
will comes on the surface of the conductor, for discharging
that charge we use the hole that will connected through the
earth,the resistance of the wire low so the size is large .

Answer / tharanidharan a

In a three pin plug ,the base two pins arranged serially are
PHASE and NEUTRAL. and the top most large sized pin is made
for grounding purpose which is used to protect the device from
shorts(high and low voltages)
example:
when a three point charger is inserted the top larger pin will
touch first than the rest so that the device is prevented by
ground

Answer / ramkumar

we know that current always choose low resistance path. as
per the resistance formula when the cross section is large
ultimately the resistance is less. another reason is the
remaining pins are designed for carrying rated currents. say
6 A. the earth terminal designed to carry more than the
rated current during fault condition.

Answer / pkb

Top point is for earthing. The hole size is large (1) to
flow fault current which is very large (2) secondly to
distinguish between phase and neutral point.

Answer / janmayjay

for return current of phase current

Answer / kandhasamy

earth connection is given soit is large

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