To reverse the rotation of a three-phase motor, you should swap any two T leads.

• A. Swap all three leads
• B. Switch the voltage polarity
• C. Swap any two T leads
• D. Invert the current direction

Answer: (C)

The rotating magnetic field in a three-phase motor comes from three AC phase voltages that are 120 degrees apart, and the direction of rotation depends on the order in which those phases reach their peaks. If you swap any two of the three T leads, you change that phase order, which reverses the direction of the rotating field and thus the motor’s rotation.

Swapping all three leads would simply relabel the phases and not change the sequence, so the rotation stays the same. Switches in voltage polarity aren’t the method for a balanced three-phase system, since there isn’t a fixed polarity for each phase like in DC. Inverting current direction across all phases isn’t a reliable way to reverse rotation either; you’d still need to alter the phase sequence by swapping two leads.