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3 phase motor fixable? 2

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Al.

Mechanical
Aug 23, 2021
17
Hi all,
Would anyone be willing to put me right on a few things? I have VERY little electrical knowledge by the way, so I apologise for my terminology...
So, I recently acquired a beautiful old drill press which I have mechanically restored. However the motor is tired.. it was completed rust-welded solid, the drill had lived under a lean-to, nonfunctional for at least 10 years. I've managed to separate it and give it a clean up but I'm sure it needs rewinding. I can see some broken strands, also there is currently a bolt driven into the windings.. also the connection leads are all useless
IMG_20210823_132122_ece8ak.jpg
, the 4 that are still there anyway. The shaft has some pitting, is that a problem?
IMG_20210821_133828_deeqs2.jpg

I'll see if I can get some photos up.
Thanks in advance.
A.
IMG_20210819_073310_cyx8c0.jpg
IMG_20210817_145359_jo1lhu.jpg
IMG_20210818_141623_cz9tzb.jpg
 
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That was my thought also, Keith. There has to be a way to mount that piece onto the end of a "C" face motor.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!
 
Providing the shaft of unknown new motor is long enough, I'm sure I could bodge it and the old mounting plate together...but I would prefer to avoid that if possible.
The old one resembled and waiting to find a nice motor man.
IMG_20210825_085737_scz3mi.jpg
 
Hi, Al,
Where are you in Italy?
We cooperate with several rewind shops in Italy.
Maybe some of them are close to you.
You can also contact us via Facebook.
ACW Facebook page
 
Thanks all. Really appreciate the advice and comments.
Hi zlatkodo, I'm in Umbria, slightly northwest of Perugia. Know anyone near there? I'm afraid I don't use Facebook.
 
Cheers edisin123,
I've got another one to do after this.. the guy I got it off has 2.. well one now, he gave me this one on the condition I fix his other one, it's in similar condition to the one I got🙃.
 
Getting old is a bitch.
Solutions that I could come up with in seconds, a half century ago now may take days to develop.
Option one:
Step one;
Buy a new "C" face motor with suitable HP and speeds.
Step two;
Duplicate the shape of the existing end piece in 1/2" steel plate.
Step three;
Drill suitably located holes and bolt the plate to the motor "C" face.
Option two:
Buy a new foot mounted motor with suitable HP and speeds.
Step two;
Mount the motor on a flat plate.
Step three;
Duplicate the shape of the existing end piece in 1/2" steel plate.
Step four;
Weld the fabricated plate to the plate that the motor feet have been bolted to.
The choice between option one and option twp may depend on price and availability of a suitable motor.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!
 
Hey guys,
Please excuse the 3 phase cluelessness, but what's the difference between the 4 pin plug that my motor had and the 5 pin socket in my workshop? Is my motor compatible with that?
IMG_20210828_080333_fiaty0.jpg
IMG_20210828_080348_mcqell.jpg
IMG_20210828_080348_mcqell.jpg
IMG_20210828_080348_mcqell.jpg
IMG_20210828_080348_mcqell.jpg
IMG_20210828_080348_mcqell.jpg
IMG_20210828_080348_mcqell.jpg
 
That was a lot of photos of the same thing...
 
Your workshop plug has three phases and a ground and a neutral.
Your motor plug has three phases and a ground.
The motor does not use a neutral connection.
The motor will run off of the workshop supply, but the plug will have to be changed.
Four round pins will not fit into five round holes. At least not this time.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!
 
Simple as a plug change... That's the right answer. Cheers waross.
 
Right answer = the answer I was hoping for.☺️
 
If you were in the US I would of said you have a trailer plug. But since you are not in the US, like most of us, I don't know.

I hope someone else has the answer.
 
With your five point socket, measure which 3 points have 3 phase voltage and connect the motor leads to the corresponding pins in your plug. Otherwise, you will end up with single phasing of the motor.

Muthu
 
Hello again all.
So, I finally got the motor back!
My next problem is I've no idea how to wire it back up.. can anyone help me out with this?
IMG_20211006_082916_unm8th.jpg
IMG_20211006_112426_g9c9fw.jpg
IMG_20211006_112007_v8cw2f.jpg
IMG_20211006_112454_d1m2mq.jpg
IMG_20211006_112443_js6on3.jpg
IMG_20211006_112417_mvrkfx.jpg
IMG_20211006_112045_fn3lbj.jpg
 
4 yellow and 3 white coming from the 2 speed switch.. the wiring diagram in the terminal cover is Chinese to me :(
Any help and advice would be much appreciated.
A.
 
Ask the shop that repaired the motor. They should know and we will be guessing.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!
 
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