Question 1054 of 844 · Washington 01 Journey Level Electrician Exam
What is the synchronous speed of a 4-pole induction motor on a 60 Hz supply?
Exactly one answer is correct.
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Correct answer to question 1054
- C: 1,800 rpm
Explanation
Synchronous speed equals 120 x frequency / number of poles: 120 x 60 / 4 = 1,800 rpm. The actual rotor speed is a little lower because of slip.
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