Answer / boopathiraj.s

Mainly Induction Motor takes 5-6 times of FLC while starting
in DOL mode.So soft starter is used to start the motor for
reducing starting current and smooth starting.Softstarter
which gives the voltage from 30% to 100% percentage of
voltage by certain time(Its in seconds) to the motor.By
means of thyristor softstarter is controlling the
voltage.After 100% voltage reached,the inbuilt DOL bypass
contactor is come into picture.
Advantages of softstarter:Motor life be good,Mechanical
equip life be good.
Disadvantage:It is mainly not applicable for heavy starting
load,Harmonics

Answer / prashant

Softstarter is used for good starting tourch with lesser
starting current

Answer / muhammad ashraf

Soft starter is a device which controls satarting Current
of the motor. it start the motor from 0 to 100% slowly.
meanwhile it save the electrical power and reduce the loses
and starting tarque.

Answer / vipupk

in this starter we using mainly 2 contrctor.

Answer / sushilkumar

soft starter also use to prevent the motor heats up & loss
of wear & tear of friction losses.
Also soft starter use to prevent the loss of power.

Answer / sushil

In soft staretr current is gradually increased which is
save the power loss & also the motor friction in
unnecessarily used.

Answer / m.a.bhatti

Soft starter is a device which controls satarting Current
of the motor. it start the motor from 0 to 100% slowly.
meanwhile it save the electrical power and reduce the loses
and starting tarque.

Answer / esveekayzee

for starting a rated motor with a DOL starter which draws 5-
6 times of load current initially which causes voltage
drops in line while a soft starter takes comparatively less
current and gradually decrease to the rated current.
but the main draw back of soft starter is its torque
remains low at the starting.

Answer / asif khan

motor life time is increased
reduces mechanical stress on motor
power is saved

Answer / ubaid

When motors starts its take 5 to 7 times much current then its rated current and produce a mechnical jerk to the winding due to which winding of motor burns soft start limts the starting current and torque and we will give step by step voltage one the motor starts smooothy soft start will bypas by magnetic contactor and motor run on full load we use soft start for better efficny and increasing the life od motor

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