Can I use a transformer to convert 110v to 240v to power a tool in my shed?

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ilyaz

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I want to build a backdoor shed next to my house that would house a power tool that requires 240v AC. I have an outside 110v outlet that sits on a 15Amp breaker. Can I power my tool by feeding 110v from the outside outlet using a heavy duty extension cord to a transformer like this and then connect the tool to the transformer? How do I calculate from the specs of the tool whether or not the 15Amp breaker would be enough and what sort of extension cord and transformer I would need?

Or is this totally crazy? :)
 
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It would depend on what the power tool was and how much current (amps) it draws.

If you just want to do this for a temporary amount of time during building of the shed or will this be a full time thing.

My guess is that it is not a good idea as there is most likely other things connected on the same 15a circuit you hope to loose and at best with your step up transformer you would cut your amps in half. That’s without any internal losses. If your power tool draws more than that it wont work.

A better plan would be to run 240 to the shed as Neal suggests.

Pros should be along with more advice for you as I’m not a pro.
 
It really depends on the needs of the "tool" that you are referring to. Although many people cross reference incorrectly 240v as both 240v and 120/240v applications.

If this existing receptacle is 120v which would be one hot, one neutral and one ground wire and is dedicated, meaning from the breaker panel to this receptacle only (this circuit is not servicing any other area such as another receptacle, lighting or anything else) it is possible to convert the existing 120v circuit to 240v only if the requirements of the "tool" are strictly only 240v. Meaning the circuit would only require two hots and a ground. If the "tool" required 120/240 for operation then this existing circuit would not be able to be converted. The other issue dictating whether the existing 120v circuit could be converted to 240v is again mandated by the requirements of the "tool". If the circuit gauge wire is 14 gauge this would limit the circuit capability to only a max of 15amps; but then again depending on the "tool" may not be sufficient.

Before we can guide you properly or even give advice you need to be more specific in the way of what type of "tool" you are referring to. If you post the tool make model and also a link to the tool online we could read the specs and give you a better idea if this is possible.

But as mentioned already running a new dedicated circuit for the tool might be best.

Do not do anything to change this existing circuit to try and convert to 240v until you have provided more detailed information.
 
Look at the tool nameplate. It should have the draw labeled on it. If it only gives you watts and not amps, take the watts and divide it by 240 and that will be the amp draw. If it's greater than 80% of 15 (more than 12), then you need a larger circuit. I admire the inventiveness of the transformer, but if it was me I'd run a dedicated 120/240V line out to the shed. Would probably be cheaper too.
 
most tools, other than industrial, can run on either 110 or 220 volts. inside the cover plate it will tell you how to connect your 110 to run the tool on that voltage. The main reason for running a tool on 220 V , is that it will run cooler and draw less amperage and therefore use smaller wires. A tool running on 220 is also more efficient, but you wont be able to tell the difference
 
A 120volt 15 amp circuit stepped up to 240 volts can only supply 7.5 amps at 240 volts.
 
Lots of good info already, thank you all!

So the "tool" is a wood lathe. I don't have one yet but want to buy in the near future.

Here's one. It says "Motor: 1 HP, 1 Ph, 11/5.5 A, 115/230 V, Prewired 115 V" so I can run it on 115V but I think a 230V would be better.

I suspect, though, that I can't get around running a separate 240v line. The outside outlet is not the only thing that sits on that 15Amp breaker so I'd probably be tripping it all the time.

I guess the "cheap" way won't work, will have to do it the right way. :)
 
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