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Yet another simple ac motor question

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New Member
I just picked up a used garage door opener and need some advice on wiring it for a custom application. Attached is the relevant part of the schematic. How would power be applied to make the motor rotate; and reverse the rotation?

Thanks much



This is a "permanently split" motor. The capacitor is used to produce a phase angle difference between the windings.

Connect the black to neutral. For one direction, connect active (hot) to yellow. To reverse the rotation, the active should be connected to orange.

Ignore the red (unless you want to bypass the protection).

For practical reversal of rotation, you could use a SPDT switch. Connect active to the moving arm, yellow to one contact, and orange to the other.


Active Member
Hi Jonasx,

Yes, Phasor is quite correct, to reverse the direction
just apply the live to the other winding.

However, its not a good idea to use a switch to do this.
These type of motors are strongly synchronous in running,
they are generally unwilling to reverse direction when
running, they just usually treat the trailing winding as
additional load, and get a bit hotter.

The motor should be switched off before reversing.
You may find that it doesn't need to stop completely,
often just slowing to near stop will be enough.

Best of luck with it, John :)
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