Little back story, I harvested this motor out of an electric pressure washer. I had to cut off a couple metal tangs on the motor and in the process took the motor apart and lost my wiring diagram.

Here is the motor Here is the motor

And here too Motor picture two

So I was hoping someone could help me figure out the wiring for my motor. the wire colours on the motor are white and black and the wire colours on the cap are white and black aswell.

Your guidance would be much appreciated.


1 Answer 1


Pretty much all AC motors which use capacitor and have no centrifugial switch require one winding connected directly to the outlet while another is connected via capacitor.

Here is a diagram (I am not sure if your motor is actually PSC, but the schematics is the same as for the other motor types): http://www.simplecircuitdiagram.com/2010/11/18/permanent-split-capacitor-capacitor-run-ac-induction-motor/

Use an ohmmeter to find out where the windings are. There should be <100 ohms between wires corresponding to the same windings (likely only few ohms) and >1M ohm between wires which correspond to different windings.

Label wires for one winding as A1 and A2, and wires for the other winding B1 abd B2. Then:

  • A1 and B1 are connected together and go to neutral wire.
  • A2 goes to live wire.
  • B2 goes to a capacitor; the other lug of the capacitor goes to live wire.

In case of wiring errors or unusual motor types, have fire extinguisher ready when turning the motor for the first time and be ready to unplug the motor if it hums instead of turning. Or connect a 100W lightbulb in series with it.

  • 1
    \$\begingroup\$ The "start" winding might be different to the "run" winding, some trial and error might be required to find the correct arrangement. And if it goes the wrong way, reverse one winding. \$\endgroup\$
    – tomnexus
    Commented Sep 6, 2015 at 7:08
  • 1
    \$\begingroup\$ Measure the resistances of each winding : one will usually be slightly (like 30%) lower; use this as the run winding (i.e. connect the higher resistance one via the capacitor). If it spins the wrong way, swap the start winding connections. \$\endgroup\$
    – user16324
    Commented Sep 6, 2015 at 11:42

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