Engineering · Electrical — Motors
To reverse the direction of a three-phase induction motor you:
- AIncrease the supply frequency
- BInterchange any two of the three supply leads✓ Correct
- CReverse all three leads
- DLower the voltage
Explanation
Swapping any two of the three phase leads reverses the rotating magnetic field and thus the motor's direction. Reversing all three changes nothing.
Authority: Marine Electrical (USCG engineering topic)
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