How to reverse a Fasco PSC motor?

[D0ZX]

I'm trying to reverse a Fasco PSC motor with a start/run capacitor. If I remove the cap I can spin start it in either direction but I want to hook it to a drum switch rather than spin starting it. Can anyone shed some light on how I would go about this?

This is a 110v 1 phase motor with 4 leads.
Black- line
White- line
Brown- to cap
Brown/white- cap

brn to brn/wh = 21 ohms
brn to white = 21 ohms
brn to black = 19 ohms
brn/wh to white = .02 ohms
black to white = 2.0 ohms
black to brn/wh = 2.0 ohms

 

[stevehuckss396]

FACT To reverse rotation of Fasco electrically reversible
models, switch the four external connectors (two female receptors
and two male plugs). It’s impossible to plug the male
plugs together, and it’s impossible to plug the female receptors
into each other. One plug goes into each receptor and, if rotation
is wrong, simply reverse the plugs.

 

[D0ZX]

Yeah, I found that too but it's not matching anything I have on this motor.
I'm thinking I need to split the coil wiring inside of it to make it happen?
Thanks

 

[stevehuckss396]

There was some text describing how to do it mechanically. Also, Not what you want.

Might be just as easy to find a second hand reversable motor.

 

[D0ZX]

I got it.
Had to open the motor up and wire the start coil to a pair of leads.
Now I can just swap polarity on those 2 leads to reverse motor.

 

[Ken I]

Just FYI

I don't know that motor but a single phase motor like that consists of two sets of windings at <90° to each other - the capacitor introduces a 90° phase shift to produce a rotating field.

So by moving the cap from one winding to the other you reverse the rotation.

All good and well.

But some motors have a start and a run winding of different ratings and are therefore only meant to run in one direction - running the other way derates the motor (look at the windings - if you can see different thickness wires this is the case).

Others use a centrifugal switch to disconnect the start winding once it starts (you normally hear it click in or out as the motor starts / stops). These normally don't have a capacitor so I don't think this is the case on your motor. These invariably have a derated start winding and should only be run in one direction - beside which rewiring to reverse is a bit more complicated.

Regards,
Ken

 

[D0ZX]

Thanks Ken
That's what I have. The motor will be running it's normal direction 99% of the time. If it smokes it I'm not out much, it was a freebie..

 

[Ken I]

Almost certainly not a problem then.

Regards,
Ken