# anyone involved in motor rewinding ?



## kennybobby (Aug 10, 2012)

Would the coils of any one phase need to be wound with alternating direction, e.g. clockwise and counter-clockwise loops, or are they all wound the same?


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## proff (Sep 22, 2015)

it depends of winding type 

for now the tools is only making simple regular winding I just build up yesterday the selection between regular coils and concentric one
but I have a lote of different types of winding to do :








https://d1f0da0d-a-62cb3a1a-s-sites...3RSW48iz-3uyRkhagomXDgaafNR2U=&attredirects=0


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## PStechPaul (May 1, 2012)

I wound a 120 VAC single phase 2/3 HP pump motor with a 36 slot stator to a three phase 8 VAC 12 pole motor. At 60 Hz it would run at about 600 RPM. I think I wound it like this:









However, IIRC, it actually ran at about 300 RPM when connected with phases as shown, becoming a 24 pole motor because of consequent poles. To have it run as a 12 pole motor, the connection to the black, red, and blue windings must be A, C', B, and then A', C, B'. That gives 60 degrees of rotation for each full cycle.

I was able to get the motor to spin at about 1800 RPM by overclocking to 180 Hz and 2400 RPM at 240 Hz. Theoretically, such a 12 pole motor might achieve 3600 RPM at 360 Hz, and six times its rated power at 60 Hz. But practical limitations such as core losses will reduce its true power to maybe 2x to 3x. Here is the actual motor:









It looks like I used a different winding scheme, with two coils in each slot and wrapped around each pole piece. I think each pole piece corresponds to a sequence like:

2A+B'+C'
2C'+A+B
2B+C'+A'
2A'+B+C
2C+A'+B'
2B'+C+A

Thus, each pole piece has one complete wrap for one phase, and then half-wraps for each adjacent phase. The pattern repeats for each set of six slots, so 36 slots will be six pole pairs (12 pole), and four pole pairs (8 poles) for a 24 slot rotor (which I also wound). I did this in 2005.


This is the scheme:


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## sdev (May 3, 2015)

Just in the process of cleaning down a 7kw motor with view to reducing voltage. I am largely influenced by Ivan's videos and forums but they are down at the moment. I need access to revise my thought train.
There is no doubt that once this is mastered, we are well on the way to a very cheap diy transport. My understanding is that Johanness Hubner's inverter will match to anything.


Will keep you posted.


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## proff (Sep 22, 2015)

sdev said:


> Just in the process of cleaning down a 7kw motor with view to reducing voltage. I am largely influenced by Ivan's videos and forums but they are down at the moment. I need access to revise my thought train.
> There is no doubt that once this is mastered, we are well on the way to a very cheap diy transport. My understanding is that Johanness Hubner's inverter will match to anything.
> 
> 
> Will keep you posted.


 yep the ivan's garage forum is now back online but very slow and the pass recovery look's still out 



my winding tool still need improvement 



nice job PStechPaul it's a dymetral winding ? the A' phase is reverted coils of phase A and you link them in series ?


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## PStechPaul (May 1, 2012)

I don't know what a "dymetral" winding is, and could not find any information. I did find "diametral" winding, but only for "moving coil" motors:


http://www.extra.research.philips.c...chive/PTechReview/PTechReview-33-1973-244.pdf


I found this thread, which explains why motors are usually wound in Wye rather than Delta:


> A delta winding should be avoided because it allows currents to circulate in a circle in the delta if the back emf wave form has odd harmonic content. This causes additional losses. Therefore, a scaled wye windings is better for high speed than a delta winding.



And, yes, the A' winding is in series with the A winding but is wound in the opposite direction to get 180 degree phase reversal. Another way to do this (and perhaps what I did) is to run an A phase wire into slot 1-2 and then back out through 5-6, then in through 8-9, out 11-12, and so on. This seemed easiest for the heavy #17 AWG magnet wire I used. I still have this motor as well as another that I wound with #18 TFFN stranded fixture wire.


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