How to Switch motor from 220 to 110 with NO diagram or plate, or colors ?

Hi Guys... I'm new here, and this is my first post. I looked thru the archives and saw a few posts about how to do this switch when everything is relatively simple, but sadly, thats not my case. I'm rebuilding an old Craftsman Joiner, but the motor with it I need to change to 110. It is a Century, in great shape, runs fine, prolly 40s-50s era, 3/4 hp, 1750 rpms, Single Phase, with dual capability of 110-220, noted on the data plate. Unfortunately, MY problem is This:

There is No schematic in or on the motor. Nor can I find ANY reference archive on the net for old Century electric motors.
There is no post plate, either, as is common; the wires come straight off the motor and are directly connected to the power cord.
ALL the wires are BLACK, except ONE of the Wires in the power cord is White, which still tells me, at least, Nothing.
I called a local electric Motor Shop, they said No problem, they could look at it and tell, but they want to charge me $80 bucks to do so; I can find suitable used 110 motors for that and less, so whats the point ?
I would like to just keep using THIS motor, its been giving the joiner good service long before I bought it and looks as if it will continue to do so for a long time to come. And I don't want to spend $80 bucks.

So, my question is, if the guys at the Electric Motor can look at it and tell, WHY can't I ? I'm no genius, granted, but I'm not an idiot. Any ideas ? Any and all help and comments are appreciated... Thanks !

DJ Moss

DJ Moss said:

ALL the wires are BLACK, except ONE of the Wires in the power cord is White, which still tells me, at least, Nothing.
I called a local electric Motor Shop, they said No problem, they could look at it and tell, but they want to charge me $80 bucks to do so; I can find suitable used 110 motors for that and less, so whats the point ?
I would like to just keep using THIS motor, its been giving the joiner good service long before I bought it and looks as if it will continue to do so for a long time to come. And I don't want to spend $80 bucks.

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Your own shop rate for a walk in, minimum billing increment of say one-hour, is less than $80?

Everybody has bills to pay. Expertly applied time is what we sell.

What justifies the $80 is having already learned what you may now have to spend one-dollar in time and searching to teach yourself. Or $100.

If you do not already have the skill to look deeper into that motor, as the shop you cited assuredly does have, it will not be easy for PM members to guide you and train you at the same time without even one photo of it, so far.

Photo, please, or it may not happen.

Bill

DJ,
Need pictures to help more. Many single phase are wired in series for 220, parallel for 110. So, for series, there will be a wirenut between two leads not connected to the line voltage. For parallel, 2 wires connected to the line and 2 wires to neutral. This can be confirmed with an ohm meter.
Joe

2 issues.

First is OCPH or operating cost per hour and that is the total of all costs to open the business divided by the amount of sellable hours.

This cost is usually 60% of advertised labor rate so the person spending 10 minutes answering the question in a $120.00 hour shop just cost the owner $20.00 with no return.

Regarding your motor.

Imagine a flash light with 2 cells.

Each is 1.5 volts and in the flashlight they are in series for 3 volts.

Your motor is dual voltage of 120/240 volts.

There are 2 windings each 120 volts like the flashlight batteries two in series add up to 240 volts.

Open the cover and take photos.

The power cord will have both windings in series and they need to be parallel.

An ohmmeter can be used yo confirm windings.

Most are same so Google motor windings to get some examples then use an ohmmeter to confirm then wire it up.

Sent from my SAMSUNG-SGH-I337Z using Tapatalk

If it is one of the old Century repulsion start motors. There are four leades comming out the side. For 110v the midle and outer leades are joined. For 220v the middle leades are joined and the outer leades go to the hot wire.

Sent from my SM-G930V using Tapatalk

Thanks all, I'll post some pics in the AM, but I think I have a much better idea of the situation... And wasn't trying to step on anybodys toes, and I have no ill will towards the shop, but they know as well as I do that motors around here used can be had for far less than $80. My impression was that was basically their "f*** off we don't want to deal with some old crap" rate and they weren't terribly concerned if I brought it in or not. And my shop rate isn't set in stone.. occasionally doing someone a solid can lead to a lot of other business down the road, and I never charge anyone to take a look at a job, initially,and I value my time as much as the next, But each to his own. I appreciate all the responses and I'll post the pics first thing.

Cheers !

DJ

DJ Moss said:

Thanks all, I'll post some pics in the AM, but I think I have a much better idea of the situation... And wasn't trying to step on anybodys toes, and I have no ill will towards the shop, but they know as well as I do that motors around here used can be had for far less than $80. My impression was that was basically their "f*** off we don't want to deal with some old crap" rate and they weren't terribly concerned if I brought it in or not.

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Not trying to step on your toes, either, but being surrounded by old motors doesn't make their rent, wages, nor utility bills any cheaper. They not only have to focus on 'revenue' work, just as anyone else must, it is wise to avoid liability or any other form of entanglement or 'comeback' in what is - to them - fossilized junque.

Hence my desire to figure it out myself. I NEED a motor for this machine, that works. I have one, now, that is unusable to me as is, adding 220 is not an option for reasons out of my control, so I'm doing what the Army taught me and finding a way to accomplish the Mission, because that is ever and always the only thing that actually matters at the end of the day. And so here I am, doing just that to the best of my ability. ;-)

DJ Moss said:

Hence my desire to figure it out myself. I NEED a motor for this machine, that works. I have one, now, that is unusable to me as is, adding 220 is not an option for reasons out of my control, so I'm doing what the Army taught me and finding a way to accomplish the Mission, because that is ever and always the only thing that actually matters at the end of the day. And so here I am, doing just that to the best of my ability. ;-)

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"Essayons"

You'll manage.

Some of my best buds are 12 Bravos... ;-)

DJ Moss said:

Some of my best buds are 12 Bravos... ;-)

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Buds are good. For sure hairy ears make a poor choice as enemies..!!!
Sort of the family business, here, 12 Alpha -> -> was.

Hang on, some of us will help. And if we don't, we can steer you to where you can get this solved. It isn't rocket science.

For now, do not disconnect anything. Do label each wire from the motor: you can use a combination of letters and numbers. Label all the wires that connect to one side of the AC line with an "A" and then with numbers; "1", "2", etc. Then label all the wires that connect to the other side of the AC line with a "B" and then with numbers; starting where you left off with the A wires. Finally use additional letters for wires that do not connect to either side of the line using "C", "D", etc. And record any connections between these additional wires, like C-D, etc. In fact, record all connections between all of them.

Then take some photos. Try to keep them in sharp focus and fill the frame with the area of interest with minimal overrun. Start with an overall of the motor. Do a second side or end if the first does not show everything. If you can, open the end where the wires enter it and try to show where they go. Also show any additional brushes, switches, fans, etc. Do this on the other end if there are any wires going there.

Now, post those photos here so we can see them. If you don't know how, here is a good tutorial: scroll down to the #8 post, it is more up to date. You may want to post your question on that board also. It is intended to help everybody with machining problems, not just pros like this board. So the reception may be a bit more friendly.

If you do not have an Ohm meter, get one and learn to use it. A fairly inexpensive one ($10 to $25) is just fine and can be purchased at places like home supply stores, hardware stores, electronic stores, Radio Shack, Harbor Freight, and many others. Trust me on not needing an expensive meter. Nor do you need a digital one; in fact for a first meter, an analog one has many advantages. I worked in TV engineering and troubleshooting equipment that was hundreds of thousands of times more complicated than an AC motor and 90% of the troubleshooting work I did with a simple VOM (Volt Ohm Meter). I have better ones, but I also still have $10 and $20 ones that I use all the time.

Hello DJMoss,
DON'T DO IT.
otrlt

otrlt said:

Hello DJMoss,
DON'T DO IT.
otrlt

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Why not? I suspect that the worst that can happen is that he will let the magic smoke, out.

wawoodman said:

Why not? I suspect that the worst that can happen is that he will let the magic smoke, out.

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If he does nothing more complicated than test his no-meter-handy guessed-at re-terminations on 120 VAC before applying 240 VAC, he won't even have that risk.

Did you ever get it figured out? I am in the same boat, got a 1 phase century motor, 2hp, dual voltage, with just a plate and no wiring diagram.Wnat to wire it up for 220v.

just try it, if it fucks up and dies, then just buy a new one then....

Tiberiusjones said:

Did you ever get it figured out? I am in the same boat, got a 1 phase century motor, 2hp, dual voltage, with just a plate and no wiring diagram.Wnat to wire it up for 220v.

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Just like the original poster, you can't expect anyone to go to the trouble of helping you if you won't go to the trouble of posting some pics of your wiring.