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Why a starter is used for a motor?
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Answer Posted / milinda4p
at the moment of start there is no rotation of the motor. So there is no back emf present. So the full voltage is applied across the winding so the current is higher( at the moment of start). In this case the starting current is more than 6 times the rated current. So the motor consumes more apparent power( for most of the industrial motors this is measured normally in kVA and metering is carried out for this seperately called maximum demand measuring. This is costed in Rs/kVA and rate is pretty much higher (In sri Lanka Rs 1000/kVA) So due to not using a startor for a motor can cause for much higher electricity bill.
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