Why motor initial starting current is high?

Answer Posted / ravi

In ac induction motor it take starting current around 7 times the full load current. The reason is during starting when we applied a voltage to stator it produce a rotating magnetic field which is rotating with its synchronous speed. The rotor speed is zero and slip is 100% so a large amount of magnectic field cuts the rotor surface and produce heavy current to flow from its and when the rotor catch its speed the amount of field cutting the rotor reduce and slip is also low and current become normal.

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