Engineering · Electrical — Motors
Star-delta (wye-delta) starting is used on larger AC induction motors to:
- AIncrease starting torque to maximum
- BReduce the high inrush starting current✓ Correct
- CReverse the motor
- DConvert AC to DC
Explanation
Starting in star (wye) applies reduced voltage to each winding, limiting inrush current and torque; the motor is then switched to delta for normal running. This protects the supply from heavy starting surges.
Authority: Marine Electrical (USCG engineering topic)
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