As shown in the illustrated diagnostic setup checking for a reversed field pole on a ten- pole synchronous motor, if a rotor is being checked after reassembly and the steel bolts repel each other as shown in the illustration, what condition is indicated? Illustration EL-0205

Correct Answer: Option A — Either coil 3 or coil 4 has a reversed polarity

In a synchronous motor, adjacent field poles must have opposite magnetic polarity to function correctly. If steel bolts placed across adjacent poles repel each other, it indicates that the poles have the same magnetic polarity, confirming that one of the coils in that pair is wired with reversed polarity.