A) B–C–A
B) C–A–B
C) A–C–B
D) B–C–A and C–A–B
✅ Answer:
➡️ C) A–C–B
🧠 Detailed Theory + Solution
◆ Step 1: Fundamental Concept
➡️ A 3-phase supply creates a rotating magnetic field (RMF) in the stator
➡️ Direction of RMF depends on phase sequence
- Sequence A → B → C → Clockwise rotation
- Reverse sequence → Counterclockwise rotation
◆ Step 2: How to Reverse Direction
➡️ Rule:
To reverse motor direction → Interchange any two phases
◆ Step 3: Apply Rule
Original sequence:
→ A–B–C (Clockwise)
Swap any two phases (example A & C):
→ A–C–B
➡️ This becomes reverse phase sequence
👉 So motor rotates counterclockwise
◆ Step 4: Important Insight 🚨
- B–C–A → same cyclic order as A–B–C
- C–A–B → same cyclic order as A–B–C
➡️ These are just phase shifts, NOT reversal
❌ Why Other Options Are Incorrect
◆ A) B–C–A → Same sequence (just shifted) → Same direction
◆ B) C–A–B → Same sequence → Same direction
◆ D) Both A & B → Both are same direction as original
🔑 Key Points to Remember
◆ Direction depends on phase sequence, not phase names
◆ Only reversing sequence (not shifting) changes direction
◆ Swap any two phases → direction reverses
◆ Cyclic shift ≠ reversal
🎯 Final Conclusion
➡️ To reverse rotation (CW → CCW):
Phase sequence must be reversed
✔️ Correct sequence: A–C–B