Answer / tariq

The above answer is correct but at some extent. The
connection is switched from Star to Delta when motor
attained it 70~80 percent speed of its full speed. The time
of attaining this speed is counted and the timer is adjusted
accordingly

Answer / dhanesh

It depends on the motor rating. Big motor requires more time
to achieve the rated rpm so the timer can be set to 10-15
sec while for small motors (upto 50HP) it can set to 8-10 sec.

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