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motor rotation

motor rotation

motor rotation

How would it be possible to change the rotation on a 110/220 motor that is 1 phase induction, class E, 2 pole?

RE: motor rotation

Others who consider this forum as their own personal stomping ground will delete this post since they can't pull out slide rule and tell you the answer. They may think your post is too trivial or not "technical" enough to meet their personal interests and give little thought as to crushing what I would consider a legitimate post for an "Electric motors & CONTROLS engineering Forum." So don't be surprised if your post is gone later today.

As for your answer, you want to swap the "start" winding leads around to reverse the direction. They are typically the red & black leads or the 5 & 8 leads.

If they are not marked as such, give me a better description of the wiring and how they are hooked up.


RE: motor rotation

With the 110v power:
The #1(white wire) supply lead connects to red+yellow wires

The #2(black wire) supply lead connects to black+white wires

In exchanging the red with the black leads I noticed no change in rotation.

Could this be one of those rare non-reversable motors?


RE: motor rotation

Did you notice if the motor sounded different or ran poorly with the swapping of your leads?

A standard single phase induction motor is reversible.
You more than likely will have to open the motor to get at the START windings. Is there a capacitor mounted on/in the motor and do you see a centrifugal switch inside on the shaft?

Is this an Asian brand motor?


RE: motor rotation

Yes the motor did start harder, hummed and when starting the second time did reverse rotation yet when starting third time turned in normal rotation.

There is a capacitor mounted on outside of the casing with a centrifugal switch in the shaft.

This motor was manufactured in Taiwan.


RE: motor rotation

From your description I had guessed you had a motor from Taiwan.

Mark each pair of leads that has continuity with each other.

Open the motor and you should see that one pair has just one wire going to each lead.
The other pair has TWO wires to each lead. This is the set we are concerned with.

Look closely and you should see that one wire on each of these leads is identical in size to the other set of wires going to the other set of leads. These two larger wires are the other RUN windings. Those two wires stay with their colored leads.

The other two wires on each of the leads, one from possibly the start switch or capacitor and a smaller wire on the other lead, are the ones that you will be swapping.

Carefully reinsulate the leads and try the motor.

If the you have nothing similar to what I described, tell me how they are hooked.


RE: motor rotation

I can’t help but wondering what/who you’re mad at.

If it’s me, I apologize for dwelling on the theoretical more than the practical. It happens that I am stronger on the theoretical side than on the practical side for motors. That’s nothing to be proud of… it’s just the way I am.

If I see a practical thread like this where I don’t know the answer I just sit back and let the folks with the experienced folks like yourself answer.  I personally have never red-flagged any thread except when tempers got totally out of control.

RE: motor rotation

My comments were aimed at those who disapprove of the more "practical" posts, since those posts seem to vanish the next day.

As for you Pete, I only wish I had as much time as you do to answer the posts. ;)

RE: motor rotation


Thanks for your time.

Popped open the motor for a better look.
Your discription was very close to that of my motor.

Red lead is connected to a White coated wire leading into the winding.

Black lead also is conected to another White wire leading into the winding.

Both White wires are approximatly half the diameter of the Red and Black leads.

Yellow lead is connected to the thin clear coated winding wire.

White laed is connected to a Blue wire going to the Start switch.

There is also another Blue wire going from the winding to the Capacitor.

Last but not least there is yet another Blue wire leading from the Capacitor to the Start Switch.

Thanks again.
I hope this gives a clearer picture.

RE: motor rotation


I remember why I hate those little motors. You have to dig into the windings to change the direction.

From what you describe, every motor lead has only ONE wire connected to each lead.

You say there is a blue wire connecting the capacitor to the WINDING. Disconnect the blue wire from the winding. Label that winding lead #5. Check for continuity on #5 and see which LEAD it connects to. From that lead it should split off to two windings (you will more than likely have to follow the lead back into the windings to find where the two are connected). Cut both of those wires from the lead and check which one has continuity to #5 (it should be the smaller of the two wires). Label that lead #8. You now have the start and finish of the start winding. Swapping 5 & 8 will reverse the motor.

To check your work, ONLY 5 & 8 will have continuity to each other. They will not show continuity to any other wires.

Reconnect the other wire back to the motor lead as it was.
Make sure the motor is properly grounded.
Cross your fingers and try it.

RE: motor rotation

steve - glad to see you're not bitter.

These forums are all of ours personal stomping ground.  The forums are specifically geared toward engineering professionals discussing technical work issues.

A very similar post to this one is contained here:


You will note this motor was for his wife's dryer.  That post does not fit with the stated purpose of this forum and I'm willing to bet this one doesn't either.

Individual members do not have the power to remove posts.  Members can only point out questionable posts to the site administrators through the red flag.  If the site administrator removes the post, it is because it does not fit with the stated purpose of the forum.

Your participation is welcome, but if you are in disagreement with the site administrators over so many of the posts, then perhaps the fault lies with yourself and not the other members of this site.

RE: motor rotation

Suggestion to ckingtools (Mechanical) Aug 5, 2002
How would it be possible to change the rotation on a 110/220 motor that is 1 phase induction, class E, 2 pole?
///Please, is there any chance that you could post the motor nameplate data?\\\

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