Answer / srikanth

Any object strating from rest position due to inertia it
requires more force is required to start. The same
principle is aplicable for electrical motors also. Current
required during the starting period will be very high which
will be 11times the actual rated current. To reduce this
strating current straters are used. star/Delta starter is
one type of starter where the motor will start in star
initially after a time delay delta connection will be
applied. by starting the motor in star connection current
required will be 1.732 times the actual current.

Answer / parth belani

When A motor starts, it draws more current, which is
usually 6-7 times the normal current. This high current can
damage the motor winding because of heating. Therefore we
need to reduse the starting current. For this purpose we
use a star-delta starter. when the motor starts, this
starter connects the motor windings in the star connection,
because of which the current reduces to 1.732 times. After
the motor picks up some predetermined speed, the starter,
with the help of a swich (this switch operates
automatically with the centrifugal force), connects the
motor windings in delta connection.

Answer / mujeeeb

ACCORDING TO MOMENT OF INERTIA ,THE MOTOR WHICH WAS AT
REST TAKES MORE CURRENT TO START IT TAKES ABOUT SIX TO
SEVEN TIMES THE NOARMAL SO IT DRAWS MORE CURRENT ON ACCOUNT
IT TAKES MORE AMOUNT OF REACTIVE POWER SO THERE WILL BE
MORE BURDEN ON LINE SUPPLYING THE VOLTAGE TO THE MOTOR.SO
WE GO FOR THE STATERS TO REDUCE THE STARTING CURRENT TAKEN
BY MOTOR,IN STAR DELTA STARTER THE STARTING CURRNT IS 1/3
TIMES OF THE CURRENT TAKEN IN DELTA CONNECTION AT
STARTING ,SO WE START THE MOTOR IN STAR AND AFTER SOME TIME
IT WILL AGAIN RUN IN THE DELTA.

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