Answer / parag bijlani

In star-delta starter, motor starts in star, and after a
time delay ,it switches to delta connections. The star
current is 1/1.732 (square root of 3).

Answer / amit kumar singh

in delta conection motor is direct on line current is
controled by relay in curcuit starting current high so used
high tourq motor as conveyr belt drive,water pump.use for
low hp motor.
in star delta conection current is redused 1/square root of
three, havey hp motor for protection heating low current is
requrid so we use star delta starter. its used for high hp
motor.
component in delta- one contactor,fuse,pushbutoon off-
on,field coil,overload relay.
component in star-3 contactor,fuse,pushbutoon, under
voltage coil,overload relay

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