How do I know if a machine has a synchronous or an induction motor?

DWQA QuestionsCategory: Induction Motor & GeneratorHow do I know if a machine has a synchronous or an induction motor?
mintu asked 6 years ago
1 Answers
Sanjeev answered 6 years ago

By visual inspection, a synchronous motor is a doubly excited motor, meaning it needs both field and armature excitation. The field windings are excited with DC and the armature windings are excited with AC. So it is a four terminal machine.
An induction motor is a singly excited machine, which has only two terminals and always excited by an AC supply.