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Categories >> Engineering >> Electrical Engineering


Question What is the d/f between DOL & star delta starter & automatic
star delta starter?
 Question Asked In Companies :: ACC, Dalkia, Indeco, Wipro, Novotel, Engineering, NINL, RMH Control Systems,     < I also faced this Question! >
 Question Submitted By :: ravi
  Answer Posted By  
in induction motor the torque is propotional to squre of
supply voltage in case of dol the motor directly connected
to supply so torque is more while in star delta the motor
is firstly connected to star hence voltage is reduced
torque will be less and when motor reaches its 80% of speed
it connects with delta with the help of timer then full
voltage is supplied hence less rating motor should be
started with dol but for high rating it should be with star

Is This Answer Correct ?    51 Yes 8 No

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