How the starter control the starting current in three
phase AC Motor?(In DC apply the reistance).
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Answer Posted / jaggu
Induction motor is similar in action to a poly phase transformer with short cktd secondary which is rotating. if normal voltage is applied to the motor then the motor will draw a large current at the start. Induction motor when directly switched on takes 5-7 times their full load current. This can damage motor winding and generate large voltage drop, which may affect other equipment operation. Therefore IM while starting uses following starters:
1) Direct online starter
2)Stator resistance starter
3)Auto transformer starter
4)Star-Delta starter and
5)Rotor resistance starter- only in the case of slip ring IM
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