AC induction motor reverse 3 phase

AI Thread Summary
Reversing the phases of a running AC induction motor causes it to act as a generator, sending power back to the source and significantly slowing down before reversing direction. This process resembles regenerative braking but is not classified as such, as it can lead to high current draw from the supply. The sudden phase reversal may also create arcing at the terminals due to the motor's regenerative behavior. Additionally, the motor could trip overloads, triggering automatic systems like standby fans or pumps. Overall, the operation can be hazardous and lead to mechanical failure if not managed properly.
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What happens if an big AC induction motor is running with full load an your suddenly reverse the 3 phase?
 
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Immediately after phase reversal, the motor will act like a generator and send power back to the source, and in doing so will heavily retard. As soon as it attain 0 speed it start rotating on the other direction. It would be like a regenerative Braking followed by direction reversal.
 
Also as you swap the terminals you are likely to draw an arc due to the regenerating nature of the motor.
 
I assume that you mean that you swap two phases over, thus reversing the direction of rotation of the motor, in a James Bond world the motor would try to turn backwards rip itself to pieces and start a chain reaction that ended with the bad guy's secret headquarters blowing up, in a real more prosaic world the motor overloads would trip, and the stand-by fan / pump would start automatically.
 
Ok thanks.

is this called plugging?

Because if it is then it is not regenerative. When you plugging you draw big current from the supply to stop to ac motor.
 
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