Several questions on soft starter, brownouts, four-pole stator, and transformer are answered. Suppose the across-the-line start resulted in only 75% rated voltage at the motor. The solid-state starter might be capable of holding the initial motor voltage to 80% instead. The result would be an increase of about 15% in accelerating torque. Reducing the voltage to an induction motor will reduce core loss. That does save some energy. But the load current will indeed go up. Four-pole stator can be rewound for six poles. How much effect transformer impedance has on motor starting capability is dependent not just on motor current, but on the total system inertia and the load torque required during acceleration.
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