Author Topic: Maybe a Conversion (Read 11578 times)

Ding123 · « **on:** August 03, 2006, 01:29:33 PM »

One of the guys I know dropped by with this motor. He was going to take it to the scrap yard because copper with no coating around here, is selling for over $3.00 /pound.SoI gave him a case of beer and a handshake for it.The shaft is

1 1/2inches thick.The motor has 36 slots,the armature is 16 inches around. It has 3 wires,blue,orange and white and they are numbered,blue #1,white#2 orange#3.If I take the armature down some I can put 24 magnets on it.2x1x1/2" Neos which I got from Wondermagnet.com. They are the nickle coated ones. I like them alot better than the

black epoxy ones.Anyway,I guess, what I want to know is, will I have to fool with the windings? I have done a couple smaller ones wired like this one and got shocking results.

I hope these pictures post this time.

dinges · « **Reply #1 on:** August 03, 2006, 08:58:40 AM »

You've left out the most important information: the nameplate data.

RPM (to determine #poles)
power
voltage
max. current.

'fooling with the windings'. Do you mean a rewind? Or finding the internal star-point and bringing it to the outside?

Ding123 · « **Reply #2 on:** August 03, 2006, 09:05:01 AM »

Hi ,Peter. I am afraid there was no plate on it so I don't know that information.Right now it just looks like my little woman without makeup...

I don't know how else to find out what I got.thanks.

dinges · « **Reply #3 on:** August 03, 2006, 09:11:18 AM »

You could try to power it & measure RPM. If it's 1500RPM, it's 4 pole; 3000RPM means 2 pole.

It's important information for determining the nr. of poles you need on the rotor. Someone experienced could probably tell the nr. of poles from the way the stator is wound. Alas, I'm not one of the people that can.

As to your little woman; I hope for you that she doesn't read this board. Or she may be a mean little woman for a while...

dinges · « **Reply #4 on:** August 03, 2006, 09:13:52 AM »

BTW, weight of a motor can tell you a lot on what power to expect.

E.g., my 3HP motor (without conversion) weighs 35kg. Now, mine has a bit more 'casting' than yours (see my 3HP conversion in my diary). But, if someome has a motor that looks a bit like yours, you could try to weigh it & compare results. Maybe if you do a google search for motors, you can find the weight in the specs of comparable ones too.

That would give you approximate power; RPM can be measured. Voltage, I assume to be the standard ones in your area.

You'll just have to play mr. Sherlock a bit...

powerbuoy · « **Reply #5 on:** August 03, 2006, 09:48:32 AM »

pick any coil and let us know how many slots it covers, a picture from a slight different angle will help.

Just from the way this head appears in the pic, I am almost convinced that this is a four pole unit ...but it's a little bit too premature to tell.

Powerbuoy

Ding123 · « **Reply #6 on:** August 03, 2006, 10:44:55 AM »

here is a picture from another angle of the coils.

Ding123 · « **Reply #7 on:** August 03, 2006, 10:47:46 AM »

It weighs 160 pounds.I don't know the Kg but maybe you can convert that.the little woman has the scales set 20 lbs light so I had to add that on....LOL

dinges · « **Reply #8 on:** August 03, 2006, 11:18:25 AM »

That's 72kg! This thing is bigger than I thought...

Like I said, mine is 35kg and 3HP. So yours seems to be at least double that.

I say at least, because as you can see in the pictures in my diary, my motor has a much heavier case. Yours is less cage/house, so more stator iron & copper.

7.5HP perhaps? At least 5HP, as far as I can judge.

Yummy yummy...

dinges · « **Reply #9 on:** August 03, 2006, 11:38:31 AM »

Powebuoy, when you reply as to the number of poles of this motor, could you explain HOW you can determine the nr. of poles just by looking at the stator?

I'd be very interested in learning this too.

Flux · « **Reply #10 on:** August 03, 2006, 12:39:12 PM »

There seems to be 3 coils per phase so it looks to me to be a 6 pole winding.

No doubt Zubbly will give the definite answer.

One way would be to feed current to 2 leads ( better still one lead to star point)

from a car battery ( with limit resistance) and explore the field with a small magnet or compass.

If you know what you are doing you can also move a strong magnet round the inside of the stator with the same pole always facing outwards and look at the kick on a dc moving coil meter connected to a pair of leads.

Flux

powerbuoy · « **Reply #11 on:** August 03, 2006, 12:48:07 PM »

Sure ...your slut config is 1:8:10:12

check out the drawing that describes your motor to the dot, it's one of the best graphics describing the 4 pole 3 phase asynchronous winding.

Let me know what you think,... its in German ...but the pic says it all ...still big for 250K ...hmmm

powerbuoy

Ding123 · « **Reply #12 on:** August 03, 2006, 12:48:36 PM »

another close up of the coils

powerbuoy · « **Reply #13 on:** August 03, 2006, 12:50:33 PM »

I forgot ... it is a four pole unit :-))

Powerbuoy

Flux · « **Reply #14 on:** August 03, 2006, 01:07:49 PM »

Yes you are right , there are 2 coil groups per phase so it is 4 pole.

Flux

Ding123 · « **Reply #15 on:** August 03, 2006, 01:32:28 PM »

I just had someone here with an ohm meter , I get the same ohm reading on each of the three wires...1,2 and 3. I think I am going to try that magnet trick...

powerbuoy · « **Reply #16 on:** August 03, 2006, 01:42:22 PM »

You are getting the same readings because the motor is internally star connected, you can see it on the very first picture if you look very closely, one of the white pieces of shrink tube has three wires going in, thats your U2,V2,W2 bridge. U1,V1 and W1 are carried out for connecting to the grid.

Powerbuoy

Ding123 · « **Reply #17 on:** August 03, 2006, 02:37:26 PM »

here are the bits of labels from the casing

vawtman · « **Reply #18 on:** August 03, 2006, 02:37:28 PM »

2 stator teeth down on the right is one coil leg and just where it starts getting dark is the other.There are 7slots open 4pl.

What is the bore diameter and length of the teeth?

Ding123 · « **Reply #19 on:** August 03, 2006, 03:17:31 PM »

I put the motor back together,took a 12 volt battery, just to see what would happen.I put one wire on negative and the other on positive..the motor tried to turn.

took the wire off spun the motor by hand,put the wire on and stopped the motor like a brake. Then I turned the motor,touched it on the positive, repeating as I could. The motor would turn slowly as I repeated this motion. I guess it might be good to fill it with magnets and leave the wiring as is. If you call it star , then that's what it is.Thank you very much.And the little woman thanks you too. She hasn't typed this much in a long time.

ghurd · « **Reply #20 on:** August 03, 2006, 03:40:34 PM »

"Big"? Looks more like huge!

G-

vawtman · « **Reply #21 on:** August 03, 2006, 04:02:28 PM »

Im guessing 25hp.Should be a good fit for a 39.5ft propLOL

Countryboy · « **Reply #22 on:** August 03, 2006, 04:52:16 PM »

If that motor is a 25 HP, it's the smallest 25 HP I've ever seen. On the farm, the cases of our 25 HP motors are over 2 feet long, and 18 inches in diameter or so. This motor might be a 5 HP or 7.5 HP.

I would not recommend using the 1X2X0.5 nickel plated neos. It will be very difficult to skew them. If you are going to use them, build a stator like zubbly did, and skew the laminations. This will require a complete rewind.

If you want to avoid doing a rewind, you will want to use many smaller magnets, so you can skew them.

If you're not sure what is meant by wiring in star, I would recommend that you DO NOT attempt to convert this motor. You will likely turn it into an expensive lesson that doesn't work. Keep studying motor conversions, and every step of the process, until you understand everything 110%. If you try to do things, but don't completely understand what you are doing, it's gonna come back and bite you.

Drives · « **Reply #23 on:** August 03, 2006, 05:08:58 PM »

This may help.

http://tinyurl.com/m9nta It looks close to what you have.

You can search from this page for AC motors.

http://www.baldor.com/products/ac_motors.asp

Ding123 · « **Reply #24 on:** August 03, 2006, 07:18:43 PM »

Yes..that is the motor..thank you for the URL.I am going to put neos 1x2x.05" in that monster. I have them already, under my pillow......lol.This has to be the greatest site on the net!for meeting people with a dream ....for doing something and sharing it with others..no matter how small or insignificant it may seem. I haven't got much to share but I'll learn along the way and maybe ,who knows, I'll be able to help someone some day...

Thanks to everyone for all your input and information today..and for taking the time

and handing out your knowledge....

thanks ,

Dave

Ding123 · « **Reply #25 on:** August 03, 2006, 07:26:51 PM »

Thanks ,Cowboy,I appreciate your comments but, I have to do what I have to do. I just looked at your files and found out what skew the magnets means.Now...I can't sleep.I want to get at it!

zubbly · « **Reply #26 on:** August 03, 2006, 07:40:45 PM »

hello Ding123,

your motor is a Baldor unit. it is a 4 pole machine. it is now connected 1 star because you only have 1 conductor on each of the 3 lead wires. it is open drip proof construction.

the shaft is not 1.5 inches unless it has been customized.

i can tell you the exact hp if you give me the following dimentions.

accurate measurement of the shaft diam.

measure the bolt pattern of the mounting feet (center to center on the side of motor)

(center to center on the front or back

end of motor)

if you can, also insert the rotor into stator and give me the measurement from center of shaft to the floor.

the maximum circuits you could re-connect that motor to is one and two circuit star delta. (this will require 12 lead wires and will give you some good options for connecting for various outputs)

it will be late tomorrow night before i can respond again.

zubbly

Ding123 · « **Reply #27 on:** August 03, 2006, 08:16:48 PM »

Thanks Zubbly, I will be out of town for the long weekend we have here so I won't be on the board until Tuesday..there is no computer where I am going,yet.There is a link to the motor a couple of posts up by Drivesdeanw. It has all the specs on the motor on that site.

I was just looking over your work as was recommended by some of the members,here.

Good stuff!!I put the motor back together, hooked any 2 wires out of the 3 up to the battery.The motor tries to turn.The same thing happens to my genny that I built with 9 coils wired in star. I think , maybe , this motor will put out power just like it is. Magnets on the armature, 3 wires to the rectifiers. Do you think it will put out power? I look forward to hearing your response on Tuesday , upon my return.'Till then

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Author Topic: Maybe a Conversion (Read 11578 times)