Reversing Rotation on a GE Motor (Capacitor Start/Run)

I have a 2.5hp GE 13.1 amp motor that I'm using to build an air compressor. It currently turns in the wrong direction and would be very awkward to mount with this turn. It turns clockwise when looking at the output shaft and I need counterclockwise.

There are two capacitors on the motor and what looks to be a centrifugal switch. Based on what I've read it seems that I can change the direction of the motor by switching the leads of the starting circuit. Unfortunately I cannot seem to find the end of the starter circuit.

What I'm able to decipher from the wires is there a three wires going in. Green goes to ground on the casing. The white joins with yellow, which splits - one side goes through the centrifugal switch where it comes out as black and goes through a philips black plastic enclosed capacitor where it comes out as black and is routed somewhere inaccessible near the stator (I think this is the starter cap); the other side joins with a blue wire next to the stator, and then passes through a steel enclosed capacitor where it comes out as orange and is routed somewhere inaccessible near the stator (I think this is the run cap).

The black wire joins to red and passes through a motor protection device prior to being routed somewhere inaccessible near the stator.

The stator appears to be affixed into the motor housing and I do not see how I can get it out to switch leads for reverse rotation.

Is it possible that all I have to do is swap the leads on each capacitor to cause the current to flow through all the wires in the opposite direction?

Any help would be appreciated. As you can see I am not and expert in this field by any means.

Thanks.

Reply to
craigpardy
Loading thread data ...

Basically yes. The centrifugal switch just breaks the start windings. See if this helps.

formatting link

--
Best Regards:
                     Baron.
Reply to
Baron

Thanks. Will I be at any risk of frying the start or run windings if I reverse the leads on the capacitors? Based on my understanding of capacitors, the current should not flow until the knee voltage is exceeded, therefore it stands to reason that the windings are in no danger of over current.

The link you sent is very helpful. It makes sense to me that I would have to reverse the leads on both capacitors - does this sound right to you?

Thanks Again. Craig.

Reply to
craigpardy

This is what you do. write down the config as you have it now.. the black wire leaving the CAP and going into the stator should be coming back out at some point joining with the BLACK from your service.. you need to switch the wires. if you disconnect the wires and use an ohm meter, you can find out which one is the starter winding. it should be a stand alone winding. switch the connections. P.S. they make some motors non revers able. normally the procedure is printed on the inside of the pecker head cover.

--
"I\'d rather have a bottle in front of me than a frontal lobotomy"

"Daily Thought:
 Click to see the full signature
Reply to
Jamie

Ok, but I am unable to find where the black wire comes out. I'll take a better look. There is no reversal schematic on the casing anywhere, so this could very well be a non-reversible.

What do you think about just switching the capacitor leads on both capacitors - do you think it will force current to change direction or cause none at all to flow?

Thanks again, Craig.

Reply to
craigpardy

if it appears that you can not find a stand alone wire to a winding that matches the other end to the CAP. then switch the yellow wire that is currently on the white wire coming in with the lead wire that is connected to your BLACK wire coming in from the service.

This way, the main winding is reversed to which side the starter cap is lead from via the switch.

If you had the model number of the GE motor, you can get the wiring codes.

--
"I\'d rather have a bottle in front of me than a frontal lobotomy"

http://webpages.charter.net/jamie_5"
Reply to
Jamie

Ok. I'll give that a shot and report back later. I'm going to switch the yellow with the red and see what happens. If that doesn't work I'll switch both capacitor leads and see what happens. I can get a serial number but don't think I can find a model number. Will let you know if I do.

Thanks. Craig.

Reply to
craigpardy

Ok try this link.

formatting link
About half way down. That animation shows only one capacitor and no CF switch. That is essentially the circuit when the motor is running. The CF and second capacitor are no longer in circuit.

Or this one. Near the bottom. Titled "Running 3-phase motors on one phase"

formatting link

The circuit will be just about right for your motor.

HTH.

--
Best Regards:
                     Baron.
Reply to
Baron

Tried switching red and yellow and I blew a 15A fuse. Tried switching capacitor leads and the motor still turns in the same direction.

I dug a little deeper into where the wiring enters the stator and it's not pretty. I'm thinking this motor is not reversible.

Just in case anyone thinks they can crack this one, I'll give my best shot at explaining the wiring:

The Black from service goes to red, through a protection switch and into the stator, where it joins with three coated wires: two large diameter and one thin wire with green coating (the coated wire I'm referring to is the actual magnet wire of the stator).

The White from service joins to yellow, which splits with one side going through the centrifugal switch and the philips plastic capacitor as black, which then joins to a small diameter coated wire, and the other side joins with a blue wire and two larger diameter coated wires. The blue wire comes back out to the metal capacitor, comes out of the capacitor as orange and joins with a small diameter coated wire.

All together I have 7 coated wire ends that I can not account for: 2 large diameter off the yellow lead, one each small diamter off the capacitors, one small green coated wire off the red, and two large coated wires off the red.

Let me know if you think this is worth pursueing. I could send my wiring schematic to someone who's interested.

Thanks, Craig

Reply to
craigpardy

Hi Craig, Did any of the diagrams in the links that I sent you help at all, particularly the last one. The circuit of that is closest to your description of you motor. Essentially you have to reverse the direction of current flow through one of the two windings.

Not easy on some motors. In the past I have actually physically turned the stator around in order to get a motor to run the other way.

If you can post your schema to somewhere I will have a look at it for you.

--
Regards:
              Baron.
Reply to
Baron

Baron,

The schematics help, but not enough. I need a lot of help. I've uploaded a wiring schematic. The question is which ends to switch with which? See what you think.

formatting link

Thanks, Craig

Reply to
craigpardy

Craig I have Emailed a diagram to your address. It should help.

--
Regards:
              Baron.
Reply to
Baron

Thanks Baron. I understand the schematic but am unable to determine where the start winding output is. I was hoping to avoid it but I'm going to have to separate the leads that join with the red wire on my schematic

formatting link
I'm hoping to establish continuity between one of those coated wires and the leads coming out of the capacitors.

Reply to
craigpardy

Do you have an ohmeter. If so you can get the information you require from using it to identify the parts. Then just mark the diagram with the information you obtain. At that point I would hope that it becomes obvious which two connections you should swap round.

--
Regards:
              Baron.
Reply to
Baron

Baron,

I do have a multi-meter. I measured the resistances between all the leads and it's a little more obvious now. Please go back to my web page link to have a look at what I measured. Both capacitors have join with separate small coated leads, which both have continuity with the small green lead joining with the main power input on the other side. The only thing throwing me for a loop is the start capacitor to green lead reads 3.6 ohms, while the run capacitor to the same green lead reads 8.1 ohms. Is it possible that there are two start windings in parallel?

Looks to me like I should switch the green and yellow leads.

Craig.

Reply to
craigpardy

There will be a difference in winding resistance and there will be a difference in capacitor values corresponding to that.

That would make sense since you only want to reverse the current through one set of windings. Just watch the insulation of the wires that you swap. You don't want any shorts.

Good luck.

--
Regards:
              Baron.
Reply to
Baron

Baron,

Thanks again. I will try the switch over the weekend and will let you know how it turns out. Worst case scenario the motor gets fried.

Thanks.

Reply to
craigpardy

Reversing the direction of current flow through a winding will not fry anything. The very worst is it will blow a fuse, and if that happened I would question whether you swapped the right pair of wires! ;-)

Just out of interest I have just started to replace a small squirrel cage motor in a dehumidifier, the replacement runs the wrong way for the fan. I just took it apart and turned the rotor round 180. Now I just have to put it into the machine.

--
Regards:
              Baron.
Reply to
Baron

It's Alive!

I reversed the wiring and all is well with my GE motor. This motor wasn't set up for a simple swap. Had to cut and join a few wires, but all is well at the end of the day. Got the reverse rotation that I need for my compressor.

Thanks to everyone for helping me through the learning process and figuring out the details. Had a lot of fun doing it. Now just to pipe together my compressor and give it a try.

Thanks Again!

Reply to
craigpardy

Glad you got it working. ;-)

--
Best Regards:
                     Baron.
Reply to
Baron

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.