A pump is run by a three phase motor, after a voltage fluctuation suddenly the motor starts moving in the reverse direction. However, the motor is connected with a single magnetic conductor for rotation in one direction. How could the motor rotate in the opposite direction? How do I prevent this from happening?
Electronic – Why would a three phase motor suddenly change it’s rotating direction
motorthree phase
Related Solutions
Finally due to trial and error I got this got spinning the other way.
I moved the jumpers shown in the pic from horizontal to vertical and swapped the white and blue wires - I have no idea why this worked!!
The reason you are noticing it is worse at higher speeds will be because of the fly-wheel effect. The energy stored in the rotating core if proportional to the square of the angular velocity... So twice as fast = four times the energy.
Momentarily shorting the leads will cause the motor to brake rapidly dissipating much of that energy as heat in the coil.
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Best Answer
You blew a fuse somewhere ahead of this pump and are now giving it single phase power. A 3 phase motor will not start with single phase power, but it will run if started some other way. Your pump likely does not have a check valve to prevent water from flowing backward, so when it is off, there is a slight back-flow spinning it backward, even if only slightly and when you energize it with the single phase power, it is already turning the wrong direction, so it continues to do so.
Find and replace the blown fuse.