Answer / vinoth

In HT motors it will reduce the starting current up to 60 percent thats why we prefer star to delta conection..........but in LT motors we use Direct online starter/.......it doesnt reduce the starting current

Answer / madhu

The starting current for motors is 6 to 7 times full load current. So start-up power will be large if HT motors are delta connected. It may cause instability (voltage dip) in case small Power system. In starred HT motor starting current will be less compared to delta connected motor. So starting power is reduced. Starting torque will also be reduced. (It will not be a problem as motors are of high capacity.)

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