re-coil a electric motor 1

[Havana Cuba]

Dear members,

I'm new here but my native lenguage is NOT English so sorry in advance for some writing errors.
I'm living also in Havana, Cuba where I'm now (please don't get jealous) you can buy any food you like over there, I'm dying for a good, large hamburger.

I need to re-coil a electric motor because of burning trough.
Sended the pump to a electrical mechanic to do the job.
Got back the pump and during the testing got a result of approx. max. 30% of it's original pressure and aprox. 1600 RPM"s.
He admitted that he didn't counted the original windings during demolision.
He copied a sort of similar electric motor.
After a few ugly words he refused to do the job again and got back the payment.
So before I go to another electric mechanical Ihave some questions.

First the specs. acc. the tag plate:

115 V, 4,2 A, 60 Hz
0,5 HP, 0,47 kW
3400 RPM
max. press. 3,2 bar


My findings:

Motor is 1-fase
Should be coiled 2 poles
Stator has 24 slots
With coil 1,575"
Intern stator radius 1"

Accoording a formulas found on the net the amount of windings should be 365.
Got a result of 3450 RPM's (matches approx. the tag plate)
And all that thanks to the internet.

Question:
Is the number of windings inclusif the SECUNDAIRY winding?

Now has the stator 8 slots filled with a thinner wire (the starting coil) located at clockwise 3 o'clock and 9 o' clock.
The other 16 slots is winded with appro. 240 in total (variing from 29 to 31 windings per bundle)


Hope you members can help me.


With kind regard,

S.J. Zonneveld
(Havana Cuba)

 

[Havana Cuba]

Warror, thanks so much for your effort bit like I've posted before, this forum likes to me more like a tea party.
People with nothing to do but reply B.
S.
I've solved my problems thanks to a real engineer I have been worked wirh in Abu-dabi

 

[3DDave]

The OP got badly screwed by the motor rewinder who should have recorded where the windings were, how many turns in each, and what the wire diameter was.

Not sure where ugly words would be necessary - just rip out the four pole windings and pack it with 2 pole.

waross - good catch on the four pole vs. two pole.

I like in the video how comfortable the guy is at making the slot insulators and hand metering the windings and yet ends up using random tools as wedges to keep the motor from rolling away. Yet, the way he has that smooth rod for his workbench and the rubber mallet at the ready suggests he has done hundreds to thousands of motors.


Here's a video of 24 slot two pole rewind:

https://www.youtube.com/watch?v=ObVw7HESVxc

Clearly the number of turns per loop changes. At the 9 minute mark or so there is a schematic showing the number of turns in each loop for both the start and run windings and the math at the end. I believe the language is Thai, but they adopted so many English words for tech that it's mostly understandable for the math.

 

[crshears]

Hello Havana, I hope you come back one last time to read this.

I can somewhat understand your disgust with these fora . . but only to a small extent.

Speaking from personal experience, I have been helped by these fora numerous times.

There is no charge to participate here.

There are centuries of accumulated knowledge, wisdom and experience available here.

You did not help your cause when you failed to mention in your first post that obtaining a new motor was highly problematic; people tend to approach issues from their own perspective, and you did not exhibit much patience with others not immediately grasping why you were going to all this trouble.

These fora are also global, so time must be allowed for worldwide participants to respond.

And people are people; not all responses will be directly apropos or address your issue.

All that said, I hope you stick around; you could learn things, possibly contribute, and hone your English skills at the same time, even though it's already quite good.

Hope this helps.

CR

"As iron sharpens iron, so one person sharpens another." [Proverbs 27:17, NIV]

 

[enginesrus]

No one answered the question about if the run and start windings are included with the count, at least that is how I understood it.

This should help a bit.

https://www.youtube.com/watch?v=2XYdTogWcIA