why do star-delta connection ?
why do not connect any circuit direct connection ?



why do star-delta connection ? why do not connect any circuit direct connection ?..

Answer / pillay

when the motor is started on star only about 60% of the
full voltage is applied across the motor winding. So the
current used is reduced but enough to start the motor with
the load.Once the motor picks up speed the current used is
reduced further, than the connections is changed through the
starer contactors to delta where the full voltage is applied
across the windings to enable the motor to function fully at
its rated voltage.
so the motor is started star and than run delta to reduce
the starting current.

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