Where is the easiest place to reverse the rotation of a 3-phase motor?

• A. Motor windings
• B. Power supply
• C. Speed controller
• D. Switchgear

Answer: (D)

The rotation of a 3-phase motor is determined by the order of the three supply voltages (the phase sequence). To reverse direction, you swap two of the three phase leads, which flips the sequence and thus the rotation. Doing this in the switchgear—the motor’s control circuit—using a reversing contactor arrangement lets you swap those lines quickly and safely without rewiring the motor windings or altering the main power feed. Rewiring the motor windings would be more invasive, changing the supply at the source can affect other equipment, and a speed controller would only help if it’s a drive that supports reverse operation. So, using the switchgear to swap two supply lines is the simplest, most practical way to reverse rotation.