# 220V table saw and wiring



## spooky1 (Jul 20, 2013)

I just moved my entire shop (military guy so I am used to it). I am in a pickle, I have a Jet tablesaw which has a three prong plug, it reads 20A 250V









on my new wall it has a female receptacle which reads 50A 125/250V









so my question is how do i make this work without burning down my new shop


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## johnstoneb (Jun 14, 2012)

Make a pigtail adaptor from one to the other.


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## ramblinnman (Feb 9, 2015)

Depends how big the breaker is, I too have a Jet cab saw and it's on a 20 amp circuit. And I would change the outlet. And thank you for your service.


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## OggieOglethorpe (Aug 15, 2012)

I'd go with the first suggestion of the pigtail… Easy to do with a prewired range plug and a receptacle.

Why?

You have a 50A circuit, and *right now*, a 20A saw. The 50A circuit can handle anything you pick up in the future requiring up to 50A. Why hamstring it? You never know when you would like to connect a heater or A/C, welder, large compressor, welder, or some other power hungry tool.


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## wapakfred (Jul 29, 2011)

Yep, the pigtail will be easy to do and the more immediate (quicker) solution.


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## HokieKen (Apr 14, 2015)

If it were me, I'd leave the receptacle/breaker alone. No problems there since the circuit has higher capacity than the saw pulls. The pigtail's a good idea. But it'll save some $ to just put a new plug on the cord coming from the saw. Lowe's lists both the plug and the receptacle for 15$. So it costs you $15 to change the plug or $30 (+ the cable) to make a pigtail (I'm sure you can find them cheaper online if you're not in a hurry). If that's the outlet you'll be using for your time in that house, there's no need to be able to plug it into another type receptacle. I'd just change the plug out and put that one up. If your next shop has a 20A circuit, just swap the plugs back out. Of course, you know you're next shop is BOUND to have a 30A circuit 

And, like Marv said, Thank You for your service!


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## Clarkie (May 11, 2013)

That outlet is for either a welder or a stove, why mess with it at all. Call an electrician and put in a 220 outlet, why Rube Goldberg it? There may be the ability also to change your saw back to 110 also, save this outlet for the big stuff, you may have or get a welder in the future.


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## bonesbr549 (Jan 1, 2010)

Technically you could just change the plug. However, I would not and here's why. You have 20A rated wiring going to your saw. Your circuit is 50A. This means if anything goes wrong and it's starts overheating, it will burn up before tripping that 50A breaker. Could mean fire and you die. Do it right, and either run another 20A circuit to your main, or, put in a sub panel, that could support your existing need and the saw.


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## OggieOglethorpe (Aug 15, 2012)

Why do so many assume a breaker protects the load where a plug and receptacle is involved?

Do you rewire rooms when you add lamps or TV's? Golly, you're really risking things if you're only using a 1 amp lamp on a 20A circuit!

Portable devices that have plugs include some sort of current protection. His saw has a breaker, probably right on the motor, other times in the switch mechanism, that protects the saw.

It makes perfect sense to size a circuit to a hardwired device. This is not one of those cases…


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## jiggles (Nov 26, 2014)

I'm with Bones….put in a sub panel. That way you can add more 120/240 lines using the correct size breakers to protect you and your loved ones. Never scrimp on quality of tools or electrical power.


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## HokieKen (Apr 14, 2015)

> Why do so many assume a breaker protects the load where a plug and receptacle is involved?
> 
> Do you rewire rooms when you add lamps or TV s? Golly, you re really risking things if you re only using a 1 amp lamp on a 20A circuit!
> 
> ...


Yep. There is no reason to downsize your circuit. If that were necessary, we would never be able to use any tools that draw less than 15 amps. A sub-panel is a great idea but is costly and entirely unnecessary. The saw has a breaker or fuse either on the motor or the switch, like Oggie said. If somehow your saw has been rebuilt and doesn't have one, put a fuse in the line no matter what circuit/receptacle you're using.

What's being suggested with changing the plug or using a pig-tail is in no way "rigging" anything up. It is entirely safe and is a proper way to do it. There's nothing wrong with a sub-panel or downgrading the circuit but there's no need for it either.


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## WhyMe (Feb 15, 2014)

That 50A outlet should be changed to a 6-50. The 10-50 is an old style range outlet that is ungrounded, that is it uses the neutral as a ground and the neutral is bonded in the range frame. This is why the outlet says 125/250V. If that circuit comes direct from the main service panel then using the neutral as a ground is not a real issue because the neutrals and grounds are bonded at the main panel, but if that outlet is off a sub-panel then the neutral should be moved to the ground bar in the sub-panel if using it as a straight 250V outlet. So there can be a little more to it than just making up a pigtail if you want the circuit to be NEC compliant. You can add at sub-panel on the circuit but it will be 250V only, no 125V because you don't have the 4th wire to get 125V.


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## wapakfred (Jul 29, 2011)

> Why do so many assume a breaker protects the load where a plug and receptacle is involved?
> 
> Do you rewire rooms when you add lamps or TV s? Golly, you re really risking things if you re only using a 1 amp lamp on a 20A circuit!
> 
> ...


Yep…what they said^^^^^^


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## GerryB (May 1, 2011)

First, IF you're renting or in a government lease, Ask for permission to change it. Get that in writing! (DAMHIKT) I'd be asking someone at work to take a look & advise me on the best way to do it. This assumes your name is not based on your job. If that is the case call an electrician. Remember, what you install (like a sub box) immediately becomes a permanent part of the structure, and cannot be removed later.
R/Gerry USCG (Ret)


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## bonesbr549 (Jan 1, 2010)

> Why do so many assume a breaker protects the load where a plug and receptacle is involved?
> 
> Do you rewire rooms when you add lamps or TV s? Golly, you re really risking things if you re only using a 1 amp lamp on a 20A circuit!
> 
> ...


I guess a tool has never shorted out causing an overload and a fire. My first house had a federal pacific panel and d breakers. I remember learning what happens when a breaker does not trip on a short.

If the circuit was a 30 am and the wiring was 20, I'd say thats pretty close. 50A is one heck of a jump. Hey if he wants to risk so be it. It's safer to at least match wire,plug,receptacle, and breaker.

Further, you go violating codes and you burn your house down, you give your insurance carrier room to do the old negligence thing on you. It's just not worth it. Just saying.

Get permission do it right, and you are covered.


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## HokieKen (Apr 14, 2015)

Actually, most lamps have 18 ga. wire which is only NEC compliant for up to 6A. The wire from the panel has to be sized for the breaker it comes off of. The wire coming from the fixture/tool only has to be sized for the current it draws, not the current available from the service.

BUT, bones has a point about the wire size and homeowners insurance. In order to be NEC compliant, anything that taps into a 50A circuit has to have 12ga or larger wire. So, in order to be fully compliant, you'd need to either swap out the breaker to a 20 or 30A breaker or rewire your saw with 12ga wire (assuming your saw currently has 14 ga which is good for up to 30A). Swapping the breaker is the cheaper option.


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## JollyGreen67 (Nov 1, 2010)

I had the same thing, and I changed the outlet and the circuit breaker. No problems.


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## rwe2156 (May 7, 2014)

Bones +2.
No can do. Huge mismatch on breaker to wire size for this machine.

You need a 20 A breaker which will protect the 12 ga wire going to your machine.

I would second the subpanel idea.

As always, consult a licensed electrician b4 you take any one's advice on a forum.


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## kelvancra (May 4, 2010)

Keep in mind the breaker is not there for the saw, or whatever else is plugged into it. It's there only for the wiring in the walls.

I'd just grab another plug and do the swap and be done with it. While the two plugs (the one you'd buy to go into the one you show and the one now on your saw) may look different, they are, electrically, the same. Of course, I'd keep the old plug for future use.



> Technically you could just change the plug. However, I would not and here s why. You have 20A rated wiring going to your saw. Your circuit is 50A. This means if anything goes wrong and it s starts overheating, it will burn up before tripping that 50A breaker. Could mean fire and you die. Do it right, and either run another 20A circuit to your main, or, put in a sub panel, that could support your existing need and the saw.
> 
> - bonesbr549


__
You didn't mention the size of breaker feeding this and you didn't mention the size wire. If the wall outlet was fed by a fifty amp breaker, the size of the wire to it should be huge, compared to 14 gauge (15 amp capacity), 12 gauge (20 amp capacity) or even ten (30 amp capacity). I just ran a new copper line to my kitchen stove for a fifty amp breaker and it's 6 gauge.


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## TheFridge (May 1, 2014)

Change breaker to a 2p20A. Change recept to a deep 4 square box. Pigtail #12s from exist wire to a new 20A 250v recept in a small round 4sq recept cover.


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## SignWave (Feb 2, 2010)

.


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## TheFridge (May 1, 2014)

Nope


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## kelvancra (May 4, 2010)

Fridge, why change the breaker, if it's six gauge wire? Why change the wall outlet and not the plug on the saw?


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## Kennyl (Apr 20, 2013)

you could make a pig tail with a small breaker box somewhere in the middle of your pig tail.I am sure there is someone on base who could engineer that for you.All of us civillians appreciate your service.


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## alittleoff (Nov 27, 2014)

If the wire is no. 12 or larger change the breaker and recptical and it will be fine. Changing the rect. Only is not correct. The recpt. is rated at 20 amps. The recp. is part of the circuit. Leaving the 50 amp breaker in the circuit is over rating the recpt. And wire going to the saw. 
The breaker is not there to protect the motor on a saw or load. it's there for the circuit which the recptical is part of. If you didn't need to use smaller breakers why even put any in. Just use the 200amp main breaker in the panel. It will hold, I ganrantee it.


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