Answer / pratheesh

Soft starter are electronic (Thyristor) devices which is
used to start electric motor smoothly. There will not be
a sudden switching of the motor to the line. Soft
startes controls the starting current and it will helps
the high current flow to the motor winding during
starting as well as it will helps the voltage
fluctuations in the electrical system while the motor
starts.

Answer / anees ur rehman

Soft starter consists of thyristers but at the time of
motor starting it limits the current 4 times.(normally at
DOL motor takes current 7--8 times.Instead of it where the
power source is limited normally VFD is used which starts
the motor from 0-1-2......50 Hz.i-e current starts from 0
and increases slowly as frequency increases per Hz.So VFD
is more better than soft starter.

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