what will be the motor terminal box connection arrangement
(star or delta). on what basis it decided?

Answer Posted / milinda4p

it may vary depending on the requirement of the
motor(whether high torque or high speed).but for an example
in a 3 phase induction motor where an high torque is needed
the rotor windings are first connected in star to get rid of
the large current(inrush) at the starting. & then after
starting it is set to delta to have a large current (because
then the voltage across a single winding is square root of 3
times that of in star=> square root 3 times larger current
in single winding) (to have a higher torque)

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