Why is starter necessary for a three-phase induction motor?
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Answer Posted / suman
small induction motors up to 3H.P.,may directly be switched on to supply mains ,but those of larger capacity must use some type of starting device or starter.the function of starter is to limit the current at the time of start, which is about 5 times the full load current this excessive current has two major upsetting effects 1. it produces large voltage drop in the distribution network and causes voltage regulation of the supply system 2.it may cause disturbance in stopping of the motor which are already running on the same supply line Four types of starting methods are employed:
1.Star-Delta
2.Auto transformer method
3.Primary resistor starting.
4.Direct On-line.
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