The ac motor is not positive and negative, so how do you achieve positive and reverse?
The switch of a single phase motor is controlled by a capacitor, and you can see it for you. Change the position of the power connection capacitor and change the starting end and the running end of the motor winding. The first floor says... Well, you can try it yourself and switch the N and L lines, and you won't be able to do the reverse rotation of the single phase ac motor. Three-phase word is simple, for example, three into a thread ABC three-phase electricity, motor is in the order of ABC to the rotation, as long as the normal operation, only in this order, just replace a. or the biggest. Or CA. The connection between the two, the motor will turn in the opposite direction
One-way or 3 phase One-way and positive inverse: commutative L and N are positive and inverse, so as long as L and N are not changed, the motor will not change. Three phases: R, S, T, three lines, any exchange of two to turn the motor. The rotation of the motor will not change without the phase sequence
Three-phase motor fixed wiring to produce a circular rotating magnetic field, single phase motors through a secondary coil series capacitor formed an elliptic rotating magnetic field, as long as the connection method is fixed, the above two is fixed in the direction of the field Change the wiring method, can change the rotation method of the magnetic field, realize positive and backward turn
Ac motor? Single item of pole type electric motor does not turn positively! Three exchanges of any two phase sequence will be easy if you have more mundane motors!
