Condenser fan motor Amp draw

[Airczech]

That motor doesn't have a "Start Winding"

Yes it does. Start or auxiliary winding, whatever you want to call it. Where do you think the capacitor is connected?

[pecmsg]

It’s a run cap. It’s energized all the time. Read the Fasco Facts!

[Airczech]

Ok, just so we are all on the same page. In a typical PSC motor, the run capacitor is connected in series with the axuilary or (start winding) , and it remains in the circuit permanently. If a start capacitor is added, it is also connected to the auxiliary winding, at the same point. Start capacitors are wired in series with a switch ( potential relay, current relay or centrifugal switch) and are removed from the circuit when the motor reaches approx. 75% of its speed.
Please refer to the attached image for the typical PSC motor internal wiring.
Start capacitors are often added to PSC motors in the field, and are commonly referred to as Kick Start or Hard Start kits.

[Airczech]

OK, maybe it should be said, that we don't add start capacitors to fan motors. Only the compressors, if the compressor has a single phase, PSC motor.
Right?

[Airczech]

It’s a run cap. It’s energized all the time. Read the Fasco Facts!

Thank you pecmsg for the attachment. Its very nice and informative. Please refer to the attached image, I circled in red where you need to do some reading.

[Airczech]

So, back to the original subject. I have Ohm-out the generic motor. You simply attach the probes of your ohm meter to the C and R terminal, in our case Black and white wire. This allows you to read the resistance of the main winding of the motor, or to see if there is any continuity at all. By attaching the probes to the C and S or Auxiliary terminal, which would be the brown wire, you can read the resistance in the auxiliary windings. The resistance in the auxiliary winding is always higher than the main winding. if you attach your probes to the S and R terminals, now you reading both, the main and the auxiliary winding. If you add the resistances of both windings, thats what you should read here, give or take a few ohms. On my motor, the main winding reads 18 Ohms. The auxiliary winding reads OL, which means that motor is going back to the supplier for a full refund!
Again, thank you all for the help and support!

[szw21]

Yes my understanding is that all split phase motors have a start and run winding. The run capacitor provides the necessary phase shift between the run and start windings to keep the motor turning. In the case of the PSC motor the star and run windings are similar in wire thickness and size of coil.

I think the only motor that does not have more than one phase is the shaded pole motor.

That's a useful little publication on motors.

[Airczech]

Yes it is. I’ll definitely keep it in my back pocket!