How much 220 power should I install?

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68bucks

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I'm covering interior walls on a new shop and before I finish I want to put one 220 vac outlet in. I don't need it now, I don't know what I would use it for other than maybe a welder or a a table saw or something like that. So I'm not sure what amp circuit to run. Any suggestions? I'm sort of thinking 30 amps would cover me for a lot of stuff.
 
Where is the service disconnect, in relation to the shop?
 
I have 100 amp 220 coming from the house to a panel in the building with its own 100 amp main breaker. This might have been better in another forum but I thought people with 220 equipment might reply with what their equipment takes. Beside a welder I'm most likely to need it for a saw or a planer or something like that I think.
 
The answer really depends on how many 220v machines you're planning on rumning off it at one time. If you're running one bandsaw with 220v that draws 13 amps, you don't need more than a 20 amp breaker. If you're planning on simultaneously running a vac that has a 10 amp draw off that same line, you're now up to 23 total amps and should probably move up to a 30 amp breaker.
 
You can run a number of 240V supplies form your 100AMP panel, however, how many corded machines are you willing to jockey around for use from a single recep.? One would think that an equip. layout and corresponding recep. would serve you better.
 
Mine is similar to yours and the outlet is a single 30A on a 30A breaker in the panel. The only thing I use mine for is my MIG welder. My outlet is right below the panel and I leave the outlet turned off when plugging and unplugging my weld area is about 20’ away but I have my welder on a cart and I extended the power in to about 30’ length. So when at my weld bench I unroll my cord when welding and if I need to I can roll the welder anyplace in the garage or out in the driveway to do work.


Without knowing what you will be using it for I would go with a 30A and I would get the common welder plug setup.


IMO it wouldn’t pay to run 240V all over the garage unless you had a plan in mind like where you wanted a 240V air compressor and then run another one to that location. Even if you are just planning a 120V compressor run its own 20A circuit to that spot.
 
start with the 30amp and that will probably be all you need. BUT if you can leave room for expansion through your cash at things like more space for circuit breakers OR ifind out what it would take to get 3phase IF it's even possible. If your like me your always wanting to try things out and your really limited by what the person did before you. Also if you can think about what things your going to have on at the same time plan for that... for example a compressor that pulls 10amps on start up and then drops to 8 amps for continued use is perfect for your circuit, but if your running a plasma cutter that draws 15 amps and you have a shop air quality fan that draws 5amps. The second that air compressor kicks on, and it will because your running a plasma cutter, boom your going to spike overload in the middle of that beautiful cut you were doing.

but 30amp 220v is totally enough for thousands of fun things like welders, plasma cutters, milling machines, lathes, lazer cutters etc.

Also as a side note, I'm pretty confident 30amp 220v is plenty for things like Variable frequency Drives, and Rotary Phase Converters if you're ever shopping use 3 phase equipment so really as long as you have space in your breaker box and are willing to run the lines it's almost better not to prerun anything and just add it as you get equipment. So I'm basically agreeing with Bud16415. Then your only spending the money on the things you use. I'm constantly down the rabbit hole of adding things because I found some deal on craigslist or the like.
 
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Thanks for the great replys. I think I'll run for a 30 amp. I'll probably just Covsr the box for now as I have no need, then get whatever I need for a plug when the time comes.
 
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