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Single phase motor - how to change direction of rotation?

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iplaya

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I'm trying to change the direction of my new single phase capacitor start 1hp AC motor.

The motor is for my air compressor, and currently rotates clock wise.

Please refer to my wiring diagram for this motor.

At this stage I havnt changed any wiring
 

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This thread might get you started.

In your motor, there is likely a centrifugal switch which disconnects the start capacitor after the motor comes up to speed.
 
The other thread buzzes me.
Would anyone know how to rewire the circuit by looking at my diagram?

Thanks in advance
 
You need to remove both bridges, and rotate them 90 degrees and refit, so that top row red connects to bottom row yellow and bottom row red connects to top row blue. Leave the capacitor connections and the mains connections where they are. The must not be any bridges to the capacitor.

You've got a 3 phase motor, being run as a single phase motor, which is quite common. You can't get full power from it, but it's a perfectly good way of running a motor.

The red wires are one phase, the yellow the second, and the blue the third. They are normally wired with the three phases to one row of terminals. Then all three connections on the other row are bridged for Star connection, or each column is bridged for Delta connection. It is possible that you will find that there are 3 bridge connectors to allow for this.

It has been connected to power the red phase directly. The blue and yellow phases are in series, and in series with a capacitor, to give it an advanced phase that starts the motor running in one direction. By reversing just the starting winding (the blue - yellow - capacitor bit) then the motor will reverse.

A photo of the rating plate would be of interest. And we would like to know if this works.

I'm afraid that I have to disagree with Mike about there being a centrifugal switch. I don't think there is one, it's just a standard 3 phase motor.
 
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If it is a three phase motor see my thread in the renewable energy section relating to how to make three phase motors run on single phase without loosing power or efficency.
 
3 phase motor

That is a 3 phase motor run in open star connection which has better starting torque this way.

You can swap one bridge or wire pair over to change direction.
 
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