Red Seal Electrician Practice
AC generationQuestion 217 of 1506

A three-phase alternator turning clockwise gives the phase sequence 1-2-3. The prime mover is reversed. What sequence results?

  1. Reversed: 3-2-1
  2. 1-2-3 again
  3. 1-2-3 at half the voltage
  4. The output stops
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Correct answer: Reversed: 3-2-1

Turning the shaft the other way makes the magnet pass the windings in the opposite order.

Source: Lessons in Electric Circuits II: AC (Kuphaldt), 7.3: Phase Rotation

Practice ac generation

Questions last reviewed: 18 October 2026