Answer / jayant mistri

It is not correct that in DOL starter, motor starts in star connection. But motor starts with Line voltage i.e 415 volts P-P in our country. It is the motor which is connected in star or delta connection from terminal box or in the motor winding.If motor is connected in star connection,each winding (R,Y and B phase) of motor, get phase voltage i.e. 230 volts (motor gives less power i.e. motor power /1.73). and if motor is connected in delta connection,each winding (R,Y and B phase) of motor, get line voltage i.e. 415 volts.motor gives rated power.

In star delta starter, motor start in star and changes to delta connection after time delay. In star connection motor draws less current as each winding gets 230 volts and when it goes to delta connection each winding get line voltage. thus star/ delta starter starts motor in reduced voltage so that motor draw less starting current. This starting is called reduced voltage starting.

Answer / k.prakashchandra

Instead of bulbs voltmeters can be employed

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