In case of 3-phase induction motors, plugging means__________?
Correct answer: D. interchanging two supply phases for quick stopping
- A. pulling the motor directly on line without a starter
- B. locking of rotor due to harmonics
- C. starting the motor on load which is more than the rated load
- D. interchanging two supply phases for quick stopping
Explanation
Plugging is dynamic braking by interchanging any two supply phases, which reverses the rotating field while the rotor is still moving. The resulting reverse torque brings the motor to a rapid stop.
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