Answer / sabaris

Normally motor takes current at the time of starting is three times of full load current.at this starting time there is no presence of back e.m.f. to compensate this effect of current.so,this much current will affect the motor windings results overheating... due to this we use starters to reduce the starting current at the time of starting..In running say 80% of its speed the back e.m.f. will generated.on that time the full vge is applied to the motor terminals to run its rated speed.
there are many starters are available depends upon the type the motor construction... i.e. star-delta,rotor resistance,autotransformer,2 point and 3 point starters,etc....

why 3phase is 440v but where as we get phase voltage 220v,we have to get 220*3=660v.can u pleas give in detailed

3 Answers   Avantha Group,

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