Single phase motor forward and reverse wiring

The structure of the 1-phase motor determines that the reverse rotation is generally completed by hardware. It is recommended to use a 3-phase motor + VFD.

A three-phase motor has three sets of coils. When it is connected to a three-phase AC power supply, it will generate a rotating magnetic field. The rotating magnetic field cuts the rotor windings and induces current on the rotor windings, and then the rotor is subjected to electromagnetic force in the magnetic field to rotate.

Single-phase motors are different from three-phase motors. Single-phase motors have only two coils, the main coil and the secondary coil. If the main coil and the auxiliary coil are supplied with single-phase electricity at the same time, the magnetic field generated by them and the force received by the rotor are the same and are in a static state. In order to rotate the magnetic field generated by the main and auxiliary coils, it is necessary to pass alternating currents with different phase sequences to the main and auxiliary coils.

But single-phase AC motors only have single-phase power, so how can we get two different phases of AC power simply and economically? At this time, a capacitor is needed to realize the phase shift, that is, a capacitor is connected in series with the power supply on the secondary coil.

For industrial high-power single-phase motors, if only one capacitor is used to both start and run, its starting torque is small. In addition, the load it carries is relatively heavy, so it is easy to cause difficulty in starting. At this time, a large capacitor needs to be connected in parallel with the running capacitor to increase the starting torque. This capacitor is called "starting capacitor".

[harrispv]

Thank you for your information, It was very helpful for me while connecting a single phase motor to reverse the rotation, keep sharing your information

[KVV]

Yep Helpful tar so now I'm looking for a switch to do both

[jumelnonod]

thank you bro your content is verry helpful

[hogboy]

thank you for making this so easy to understand

[brucea]

forward wiring does not make sense as the both N and L are shorted together.

[LElf-ezxz]

I have same problem. Instead i connected the fase in u2.
Guess what happen?😂😢

[andrewdavid-RYH]

Hello, can you help me understand how to wire ATO single phase VFD to my Jet Drill press Single phase motor.

My motor specs are, 230 V, 4 A, 3/4 hp, 1400 rpm.

I have watched the videos, but still can’t figure it out. Thanks

[nathanielwinkle]

Can anyone please tell me if you have to disconnect the capacitors if you fit a vfd, thanks

[camerondentremont]

Can someone tell me where this soundtrack is from?

[alistercarmichael]

Two comments further down.
I looks like upon reverse there is a dead short between L and N supplies.
As the author says. The connections are external to the components so the rewire disconnects what looks to he a hardwired node. These two point are not connected as per the schematic.
In the forward drawing the main winding is electrically reversed.
The difference between forward and reverse is the "polarity" of the main winding. There is a 180deg phase shift being applied to one winding, and this effects the change in magnetic rotation.
The same could happend by changing the function of each winding. However it is easier to breakout only two wires from the main winding and reverse them if you need an external direction control.
Thank you for the video and graphics.

[peteryao]

0:50 the forward wiring is NOT correct. Please correct it before anyone really follows this and burns something.

[mar-tin]

You have reversed the main winding instead you need to reverse the starting winding