Answer / manoj

at the time of starting there is high magnitude of current
flowing in the stator winding.this is about 5 to 7 times the
full load current.such large current may harm the
equipment.this high value of current may cause objectionable
voltage drop in the power supply lines feeding the
equipment.so starters are used to minimize the abrupt
increase of the current.

Answer / thirudinesh1982

in the motor initially stable when the motor get power then start to rotate at the time starting current 6 times greater than normal current because (there is no back emf at the initial). So we protect the motor from the inrush current to use the starter.

Answer / kundanmalani1990

Initally the motor current r the 6 to 8 % high to the rated value so that starter r use to the starting current limit .and protection of the over voltage so the starter r use .i think

Answer / harini

To limit the starting current in motors.Because at starting
high currents will flow in motors.That current is 15-20
times more than that of full load current.

Answer / dhanush d

In a 3 phase induction motor,the magnitude of the induced emf depends on the value of the slip.
At start a large emf is induced in the rotor circuit
Stator consequently draws a large start starting current which is 5 to 8 times the load value.
This may damage the motor as well as the components in line with it
Therefore,a Starter not only limits the starting current but also provides protection against low voltage and high load condition.
At the beginning the 6 ends of the three phase windings are brought out and connected as Star connection this reduces the voltage in each phase by 1 /√3 times the value it would,if it was in delta connection.
And tge starting current reduces to 1/3 of its value.
but the torque also reduces.
As this method is cheap, its used in mixers abd drills.

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