Electric motor wiring...w..t..f...

[S&S_Work_Saws]

So I've been packing around this really cool old 1960 electric motor with me for years and years. I found it under my grand father's work bench after he passed away. So I never got a chance to ask him about it.


So I'm trying to get it hooked up and running again. I've never seen an electric motor I couldn't figure out....until now. This thing is 115V. Says it needs a 20S condenser on the tag. So I'm assuming a more modern capacitor could be used.


I took it apart to try to trace some wires, and found it has a centrifugal single wire starter switch. That switch has a yellow wire going in and a blue wire coming out.

So I've got for wires going into this 115v motor ...
-Black x 2
-Blue x 2 (one of these comes out of the start switch. It's yellow into the switch, blue out of it)
-Tan x 1


Looks like there in 2 windings to me. A black and blue wire going to each side and the tan going between them. I'm assuming the tan will be the neutral wire. Now how should I hook the rest of them up to 1 hot leg with a capacitor??
I'm open to any and all suggestions.

 

[SimonHS]

Bodine Electric is still in business. You could ask them. They may have a copy of the schematic for that motor in their archive.

Gearmotors - AC & DC Electric Gear Motors - Bodine Electric Company

Bodine Electric Company is a leading manufacturer of fractional horsepower gearmotors, motors, parallel shaft gearmotors, and motor speed controls. Bodine Electric offers over 1,300 standard products and thousands of custom designed gearmotors, motors, and speed controls.

www.bodine-electric.com

 

[Al Smith]

From what I gather you've stumbled on to a gear reduction unit drive motor .Made to drive a gear reducer .With only 1/15 HP it would only have the power of a sewing machine motor .The start cap only needs to be close .Too small it won't have much starting torque .Too large it might cook the start winding .
Other then the novelty this thing needs to be coupled to a reduction unit or a belt system with a rather large ratio of speed reduction .Used as a direct drive quite frankly 1/15 HP wouldn't power a pizz ants motor scooter .

 

[Sloughfoot]

This post brings back nightmares of a recent air compressor restoration project.

 

[Al Smith]

I forgot to mention but if you Google Bodine electric pictures will show up showing the entire reduction unit with a similar motor to this one.

 

[S&S_Work_Saws]

I tried reaching out to the manufacturer but they have never returned any of my calls or emails.
Sorry, I should have included a picture of the entire unit. It does in fact have the gear reduction unit attached to it. That's what I thought was kind of neat. It's a 90° output angle. I'll post a picture shortly.

 

[S&S_Work_Saws]

Not sure what it was originally used for but it was probably under my grandfathers work bench for a lot of years. He probably wouldn't figure out the wiring either lol

 

[S&S_Work_Saws]

Not sure what it was originally used for but it was probably under my grandfathers work bench for a lot of years. He probably wouldn't figure out the wiring either lol

 

[Al Smith]

I think you're thinking too deeply .It appears to me as just a single phase motor using a cap start and a start switch . Just put it back togeher and give it a go .If it won't start change the capacitor .Reading the spec tag it could be a cap start cap run motor then the larger 20 Mfd would be the start and the smaller 7.5 Mfd would be the run cap .

 

[S&S_Work_Saws]

Whole motor

 

[S&S_Work_Saws]

I think you're thinking too deeply .It appears to me as just a single phase motor using a cap start and a start switch . Just put it back togeher and give it a go .If it won't start change the capacitor .Reading the spec tag it could be a cap start cap run motor then the larger 20 Mfd would be the start and the smaller 7.5 Mfd would be the run cap .

I thought about that but was afraid of burning it up and thought there was possibly a way to figure exact what wire is what.

 

[Al Smith]

Your going to need to trace the wires out to be certain .Trying to trouble shoot on just a photograph is rather "iffy " .I assume the start switch is between one yellow wire and one blue wire .Assembled the start switch is held closed until it reachs a certain speed then the switch opens it up removing the start winding plus the start cap from the circuit . On a single phase motor a combination of the start winding plus the cap cause a "phase shift " of about 30 degrees which provides rotation .Fact being if it were not for the reduction unit rotation could be established by a rope around the shaft as if it were a gasoline engine on a lawn mower . With that stub shaft and a 12 to one reduction you might be able to rope it over fast enough to start it .

 

[S&S_Work_Saws]

Got it running finally. After about 15 emails to Bodine electric. They told it was a custom motor produced by a company in California and they have no info on it. After a few more emails I was finally given a wiring schematic for it. I'd have never figured it out. Uses 2 seperater capacitors. Manufactured 1964. Runs as good as the day it was built.
I'll share the diagram in case it helps someone else down the road.

 

[Al Smith]

This is probably it----https://circuitglobe.com/capacitor-start-capacitor-run-motor.html

 

[S&S_Work_Saws]

I'd have never guessed this schematic and using those wire colors. Still unsure on exact capacitor size requirements. I have a box of used capacitors. I just started grabbing them and trying them until I found 2 of them that made it come to life.

 

[Al Smith]

Usually the run cap will be oil filled and the start cap,larger will be electrolytic .

 

[S&S_Work_Saws]

Usually the run cap will be oil filled and the start cap,larger will be electrolytic .

I learned something new today. I never knew that. I know one or both of the capacitors I hooked up to it said "contains Castor oil".

 

[Al Smith]

Castor is only one type oil which is nontoxic .However some older caps and transformers used a product called


Askarel which has environmental problems and has been connected to cancer .Usually if you find one of those it's labeled some place on the cap. Oil caps are sealed units and for all intents if it's not leaking they are good to go .If it is leaking it will fail sooner or later .
Caps are an interesting item and are used for number of things besides starting a single phase electric motor .For example I rewired a three phase DC welder ,400 amp to operate on single phase .In doing so I made a double Pi type filter to remove the AC ripple using two big oil caps and a large inductor .Smooth as silk but missing the three phase rated at about 225 amps which is enough .

 

[lehman live edge slab]

Only time I used caps on much when I was younger was car audio to store up energy for the hard amplifier draws. I’m not sure if the ones in an electric motor work the same or not but I’m assuming they just store the energy also for a hard draw like start up.

 

[Al Smith]

Using water analogy a cap works like a pressure tank on water or air .