why is used for starters for staring motors?

Answer Posted / priya

Starters are used to limit high currents during starting by adding resistors in series with armature circuit which are excluded gradually when the motor speed increases. High starting currents are due to
1. In case of DC motor, initially back emf(E) is zero therefore I=(V-E)/Ra becomes V/Ra. Generally Ra armature circuit resistance is very low hence I is very high during starting. When speed increases back emf increases and I reduces therefore resistors can be excluded.
2. In synchronous motors starters are not used

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