# Six Lead/Two Speed Motor



## eutecticalloy

Okay, I know there was a thread like two weeks ago on this but we have a ton of these motors where I work. So I just want to be clear. From the diagrams below it looks like each phase has four coils off leads T1, T2, T3, and all phases connected in wye. In the the middle of series connections there is a lead brought outside. These make up are T4, T5, T6. 

So for a high speed connections you short T1,T2, T3 and apply line voltage to T4, T5, T6, making a parallel connection of two windings on each branch of each phase.

For low speed apply line voltage to T1, T2, T6 and leave T4, T5, T6 open, connecting all stator windings in series for each phase.

My questions is in the low speed configuration all current will travel in one direction through all four stator windings, but in high speed configuration the current will travel in half the windings the same way as before and the opposite direction on the other half the windings. 

Won't these "rotating magnetic fields" fight each other in high speed configuration, assuming they match each other in low speed configuration?


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## SteveO.

The motor you've posted is a variable torque, consequent pole motor. When you're in low speed (series wye) the windings are connected so that the magnetic fields travel through the windings and create a twice as many "poles" as you have in the high speed connection. When you increase the number of poles, you decrease the speed of the motor. In high speed, the fields travel in a way that you have the minimum number of poles and the maximum speed, and in the case of this motor, maximum torque. These are usually used for loads like fans that require less torque at low speed and higher torque at higher speeds.


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## Motorwinder

Consequent poles develop a "ghost pole" between the groups. When we wind 4 pole consequent pole motors, we insert 6 groups. Normal salient 4 pole has 12 groups. The 6 groups are all hooked in the same direction. All north poles. You get the south poles between the groups consequently. Giving you 12 poles or 4 poles per phase. 

Maybe an engineer could explain it better.


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## Awg-Dawg

Just marking this page for future reference.


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## nolabama

subscribed​


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## eutecticalloy

Motorwinder said:


> Consequent poles develop a "ghost pole" between the groups. When we wind 4 pole consequent pole motors, we insert 6 groups. Normal salient 4 pole has 12 groups. The 6 groups are all hooked in the same direction. All north poles. You get the south poles between the groups consequently. Giving you 12 poles or 4 poles per phase.
> 
> Maybe an engineer could explain it better.


Can you draw a diagram? With pole references?


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## Motorwinder

eutecticalloy said:


> Can you draw a diagram? With pole references?


Best I can do on my lap-top. I'm moving and changing jobs, so my main computer is packed away.


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## John Valdes

I notice you guys have taken a special interest in motors and how they are wound. I have found over the years that I do not need to know to much about the winding aspect as much as connecting of the motor correctly to the supply. Wye start, Delta run starting being the most misunderstood of all the motor starting methods and the one that gives us as electricians the most trouble connecting is a prime example.
We have enough on our plates and IMO we do not actually need to know what the motor shop does, unless you just want to know. Just to know.
Motorwinder does this for a living. It is a discipline of its own. Even in a manufacturing or commercial setting, we really would never actually work on a motor. We have in the past replaced bearings and never checked the tolerances like a machine shop would. Yes, all good motor shops also have a machine shop or they sub it out. So, that right there shows we were doing that wrong. Just installing a bearing does not always fix the problem and could make things worse than they are.
Once we have determined we have a bad motor, our responsibility as far as repair of this motor no longer lies with the electrician. It lies with the motor repair shop. We are done.

I guess what I am trying to say is all this winding information while great to read and learn about is not our job. We do not need to spend hours, weeks or days trying to understand this discipline (motor rewind). To learn a new trade.
If you are that interested, you might consider finding work in a motor shop and learning this new trade. It is a new and different trade. That is why I always have a reliable EASA shop on call 24-7 just for motor issues. This is their work not ours.
Having spare motors around is a big help as we can install the replacement and then send off the bad one. Hopefully we have discovered why the first motor failed before we install the replacement motor. This why we have motor shops.


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## SteveO.

John Valdes said:


> I notice you guys have taken a special interest in motors and how they are wound......


I agree that we wouldn't ever pull one apart but knowing how they're wound goes a long way to understanding why they work the way they do as far as their Hp ratings, speed ratios, starting characteristics, torque ratings, etc. If you didn't know how the OP's motor was wired for both speeds, or even how to identify it, you'd have a tough time choosing the right starter and wiring it. 

I think it's important to understand a motors construction so you choose the motor best suited for the load you're driving.


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## Motorwinder

It's good that some electricians take an interest in motor operation. We get so many electricians that don't have a clue why their motor burnt up. Or know their connections.

The easiest way to understand a wye start delta run motor for instance, think of the euro motors. The wye is always the higher voltage connection.

So a delta run motor that runs on 460 volt, would have a wye connection close to 800 volts. So starting it on wye, is like starting on half the voltage.

I like visiting this forum. I know mine is a different trade, but like learning new stuff. And I've learned a lot from you guys, that has helped me in the day to day operations in the shop.


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## eutecticalloy

John Valdes said:


> I notice you guys have taken a special interest in motors and how they are wound. I have found over the years that I do not need to know to much about the winding aspect as much as connecting of the motor correctly to the supply. Wye start, Delta run starting being the most misunderstood of all the motor starting methods and the one that gives us as electricians the most trouble connecting is a prime example.
> We have enough on our plates and IMO we do not actually need to know what the motor shop does, unless you just want to know. Just to know.
> Motorwinder does this for a living. It is a discipline of its own. Even in a manufacturing or commercial setting, we really would never actually work on a motor. We have in the past replaced bearings and never checked the tolerances like a machine shop would. Yes, all good motor shops also have a machine shop or they sub it out. So, that right there shows we were doing that wrong. Just installing a bearing does not always fix the problem and could make things worse than they are.
> Once we have determined we have a bad motor, our responsibility as far as repair of this motor no longer lies with the electrician. It lies with the motor repair shop. We are done.
> 
> I guess what I am trying to say is all this winding information while great to read and learn about is not our job. We do not need to spend hours, weeks or days trying to understand this discipline (motor rewind). To learn a new trade.
> If you are that interested, you might consider finding work in a motor shop and learning this new trade. It is a new and different trade. That is why I always have a reliable EASA shop on call 24-7 just for motor issues. This is their work not ours.
> Having spare motors around is a big help as we can install the replacement and then send off the bad one. Hopefully we have discovered why the first motor failed before we install the replacement motor. This why we have motor shops.


Motor Winder does wind motors and yes understanding as much about the electrical industry is my job, at least thats what I tell myself


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## eutecticalloy

Motorwinder said:


> Best I can do on my lap-top. I'm moving and changing jobs, so my main computer is packed away.


these are diagrams that I made


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## SteveO.

eutecticalloy said:


> these are diagrams that I made


You're close, but your labeling is off. 1,2,3 are labelled clockwise and then 4,5,6 go ccw. I'm on my phone or I'd draw it out.

Edit... I guess I wouldn't really need to draw it out: All you need to do is switch 5 and 6 and then your drawing is labelled correctly. Tough to see what's going on through the phone..


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## Awg-Dawg

John Valdes said:


> I guess what I am trying to say is all this winding information while great to read and learn about is not our job. We do not need to spend hours, weeks or days trying to understand this discipline (motor rewind). To learn a new trade.


 
Even though I have wired alot in my life,I never knew how a transformer worked until about 10 years ago.

So, now I am trying to get a handle on motors work.


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## micromind

In my experience, motors are the most misunderstood electrical devices of them all. Most guys can properly connect most motors, but anything out of the ordinary becomes a challenge that they will likely lose.

For example, I've gone on quite a few trouble calls of a new motor that doesn't seem to develop enough power. Almost always, it's a 12 lead motor that has been connected wye and run across the lines. I guess they figure that since the incoming power is wye......

Another one I've done a number of times is use the motors windings as an autotransformer. By this I mean operate a 120 volt light or coolant pump using the windings of a motor that runs on 240 or 480. 

I've also seen a number of mistakes made with starters. Sometimes the timer in a wye-delta starter will be replaced with a standard timer that doesn't have a transition delay.

A relatively new set of problems stems from VFDs. I realize that a VFD is the whiz-bang cure for ANY motor problem......lol.......but seriously, I've seen a lot of trouble caused by improper installation of a VFD. Very few electricians (and even fewer engineers) know how to properly design a motor/VFD system.


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## Motorwinder

SteveO. said:


> You're close, but your labeling is off. 1,2,3 are labelled clockwise and then 4,5,6 go ccw. I'm on my phone or I'd draw it out.
> 
> Edit... I guess I wouldn't really need to draw it out: All you need to do is switch 5 and 6 and then your drawing is labelled correctly. Tough to see what's going on through the phone..


The drawing is correct.except, 7,8,9.

A- 1-4-7-10
B- 2-5-8-11
C- 3-6-9-12


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## Motorwinder

Link didn't work


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## eutecticalloy

Motorwinder said:


> Link didn't work


Yeah I get the nine lead and twelve lead motor winding It's just this unusual six lead motor. Its from Germany by the manufacturer Stephan like I said before we have to make an external connection in one of the two speeds.


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## SteveO.

Motorwinder said:


> The drawing is correct.except, 7,8,9.
> 
> A- 1-4-7-10
> B- 2-5-8-11
> C- 3-6-9-12


It's only a 6 lead, consequent pole motor, variable torque. Pretty sure his drawing is right except for 5 and 6 being reversed. It's not a dual voltage motor. :thumbsup:

The image you posted is a totally different motor.


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## eutecticalloy

SteveO. said:


> It's only a 6 lead, consequent pole motor, variable torque. Pretty sure his drawing is right except for 5 and 6 being reversed. It's not a dual voltage motor. :thumbsup:
> 
> The image you posted is a totally different motor.


So SteveO, in which direction will current flow through the windings let's say on L1 at it peak in both connections?


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## SteveO.

eutecticalloy said:


> So SteveO, in which direction will current flow through the windings let's say on L1 at it peak in both connections?


It's tough to explain because the motor isn't physically wound the same way it's drawn schematically, but in low speed, the windings are in series and create 4 "poles" inside the motor. The current between two adjacent windings is always opposite so they create a pair of poles together. In high speed, the windings are in parallel, create 2 poles and will spin twice as fast. The poles are more seperated and the field will travel across(through) the rotor and in to an opposite pole. 

In high speed, you have more torque and more Hp because you're applying more energy to each winding. In low speed you'll see half the speed, less torque and a quarter of the Hp as high speed because the windings are series connected. 

Maybe this drawing will help, but I can try and explain it differently if it doesn't. From the drawing, you can see that in one connection you get current flow through both windings in the same direction but when you put them in parallel, the direction changes through one of each pair.


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## eutecticalloy

SteveO. said:


> It's tough to explain because the motor isn't physically wound the same way it's drawn schematically, but in low speed, the windings are in series and create 4 "poles" inside the motor. The current between two adjacent windings is always opposite so they create a pair of poles together. In high speed, the windings are in parallel, create 2 poles and will spin twice as fast. The poles are more seperated and the field will travel across(through) the rotor and in to an opposite pole.
> 
> In high speed, you have more torque and more Hp because you're applying more energy to each winding. In low speed you'll see half the speed, less torque and a quarter of the Hp as high speed because the windings are series connected.
> 
> Maybe this drawing will help, but I can try and explain it differently if it doesn't. From the drawing, you can see that in one connection you get current flow through both windings in the same direction but when you put them in parallel, the direction changes through one of each pair.


Thanks man. I think I understand it much better now.


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