How is the forward and reverse rotation of the motor achieved? What is the electrical control principle behind it?
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How is the forward and reverse rotation of the motor achieved? What is the electrical control principle behind it?
Previously, when adjusting the forward and reverse rotation of the motor, it was sufficient to simply swap any two of the three-phase connections; as for what equipment is used to achieve this, I’m not quite sure
Use two contactors to control the same motor; just ensure that the phase sequence of the contactors is opposite
The forward and reverse rotation of a three-phase asynchronous motor is achieved by changing the direction of the rotating magnetic field generated when the stator windings are energized. In practice, this is achieved by changing the phase sequence of the power supply. In the contactor control circuit, two contactors are used: one to control forward rotation and the other to control reverse rotation. The difference in wiring between these two contactors lies in the phase sequence at their load terminals (one uses ABC, while the other uses ACB). You can search for the schematic online to find out more.
A commutation switch can be used for this purpose, as well as a contactor. Two contactors, connected in opposite ways, can be used to adjust the phase sequence; it is also possible to manually adjust the phase sequence on the wiring box.
In three-phase four-core or five-core wires, any two of the A, B, C phases can be swapped in place