Converting Unisaw to run on 120V

Jul 16, 2004 19 Replies

I have a 3HP X5 Unisaw and would like to know if it is possible or if anyone has had experience converting or reconfiguring the motor to work on 120V as opposed to 220V?



The saw and the remainder of my belongings will be doing a 6-month tour of duty in a "temporary" residence as I explore the local real-estate market. The conversion is less a choice and more a lack of options as 120V outlets are everywhere but there appears to be only one 220V circuit in the house and that feeds the AC. I could certainly just hijack the 220V circuit but the fact that it is not my house makes me want to explore other possibilities before taking that step. Not to mention the pre-emptive "LEAVE IT ALONE" from SWMBO.



Whole thing is very depressing as I just got the saw a few months ago and have been tricking it out and doing really cool stuff with it ever since - and now I have to take it down, move it and possibly neuter it for a short time.



Thanks in advance for your help . . .



L

Nope, not going to happen. OTOH, 220 availability might just be a case of using the wires from breaker to the box you choose. They even make regular size 220 breakers versus ganging now.

I don't know if it is "possible", but it is not reasonable. You would need a 30 or 40A circuit, and that would be much more difficult than a 240v circuit.

Yeah, Ralph Whatshisname did it about 6 or 8 months ago. Swapped in a Craftsman 3.5 hp motor and made it direct drive. Ed

LOL ... around here that's otherwise known as the "Mexican framing crew method" of getting 220v to a piece of equipment on a building site.

They typically run a single wire from alternate sides of two 110 receptacles on the "t-pole", and keep stabbing different receptacles until they finally get a hot wire from each leg and the equipment runs.

Definitely NOT recommended ... but I'd gladly take a nickel for every time I've seen it done. :(

why not just put a breaker in teh panel and add a 220 outlet to the garage? The cost is minimal.

Tks Joe

I saw a commercial device for doing that. I thought it had to be a transformer or something until I read the description.

This is what I was thinking and just thought I must be missing something. As long as there is a double slot in your box, stick a 220 20v breaker in there and run the two (both hot) wires from it and the other from the bus ground to a 220 wired outlet and you're good to go.

Don

OK, I've got a weird, and probably impractical, idea. In the breaker box you have two seperate hots to provide 240v. The breakers alternate between hots. It seems possible, although maybe not wise, that you could take two extention cords, plug them into two outlets from different breakers (and hots), cut off the female end (not in that order), install a 220v female end and then plug it into the saw.

Not sure if I'd want to try this (enough disclaimers yet?) but I don't see why it wouldn't work. Of course if the breaker tripped you'd still have one hot wire.

Don't need a double. They make a standard size.

As long as the garage is on a separate circuit, why not use the existing wiring for 220 to the first box, 110 legs thereafter.

That's interesting. How does it connect to both phases / hots? Or is this for a new type of box that has both phases available to each slot.

What you just described is basically the "Mexican framing crew" 220v "plug". It works in a pinch, but no ground, and not something you would recommend except in an emergency situation.

Thanks everyone for your input. I have thought VERY seriously about tapping into the AC circuit and calling it a day. Putting another breaker in the panel is not an option in this case as the panel is "full". I think my best bet is to talk to the property owner and get his blessing to have an electrician tap into the AC circuit as it is existing and a junction box, a couple feet of #10 AWG and some splices will about do it.

Thanks again . . .

L

Larry...

My Unisaw came with directions for both 120V and 220V wiring. The

3HP Unisaw at start up draws 20A when wired for 220V and 40A when wired for 120V. It's possible (I tested it); but not very practical.

Best solution is to add a 220V circuit if you possibly can.

someone told me it was not technically the Mexican framing method unless they were using speaker wire.

For many years I've had a heavy extension cord, three insulated conductors (#10 awg) and a ground. About like you see at the carnival running the rides. When I'm going to be somewhere a short time, I install a couple of breakers and a 50 amp outlet right next to the box. The cord gets the juice to my tools. On the other end of the cord I have a piece of wood with several outlets on it 120 and 240. When I move on, it's pretty simple to remove the outlet next to the breaker panel and leave no evidence. I don't leave a bunch of wire I've purchased routed through holes in joists or whatever. I'll probably leave the breakers rather than the open holes where the knockouts have been removed.

rhg

R> OK, I've got a weird, and probably impractical, idea. In the breaker

FWIW, you can buy inserts to fill those holes. If you can't find them at Lowe's or HD, try

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-- Regards, Doug Miller (alphageek-at-milmac-dot-com)

Get a copy of my NEW AND IMPROVED TrollFilter for NewsProxy/Nfilter by sending email to autoresponder at filterinfo-at-milmac-dot-com You must use your REAL email address to get a response.

Ease up on that Polish stuff.

Had a pair of recent retirees move in a mile up the road and a quarter mile back. I'd only met them briefly, but I can report with confidence their ethnicity is Polish after the appearance of two plastic flamingos as driveway markers.

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