PDA

View Full Version : 220/240 in shop



DCP
01-30-2019, 09:43 PM
Want to put 220/240 in the shop

No tool in that voltage yet, do I wait to and put in what amp They needs or put in 40 or 50 amps?
I don't know a lot about 220/240 lots of different amps out 20 30 40 50 amps maybe even more.

Can you put a 50 amp plug on a 20amp tool?

Thanks, DCP

country gent
01-30-2019, 10:38 PM
I am planning on 4 220 outlet in the new building. as 2 will be for welders 1 for air compressor and 1 extra. This may change as I may hardwire the welders and air compressor in. then it will be 2. Remember if you go with plugs they need to be rated for any tool that may be plugged into them.

Hannibal
01-30-2019, 11:00 PM
Want to put 220/240 in the shop

No tool in that voltage yet, do I wait to and put in what amp They needs or put in 40 or 50 amps?
I don't know a lot about 220/240 lots of different amps out 20 30 40 50 amps maybe even more.

Can you put a 50 amp plug on a 20amp tool?

Thanks, DCP

Keep in mind you can always put in 6 gauge wire and put a 20 amp breaker on it, but you can't put in 10 gauge wire and put a 50 amp breaker on it. Well, you CAN, but a fire will likely ensue.
When I built my shop years ago, I pre-wired it for 220V near all 4 corners and just left the feeds disconnected until I had something I needed one of them for. If your not comfortable doing the wiring yourself, this may not be a viable option for you.

Just a suggestion. Hope your project goes well.

NoZombies
01-30-2019, 11:23 PM
Can you put a 50 amp plug on a 20amp tool?


You can plug a 20 amp machine into a 50amp circuit, but NOT the other way around. Well, not without having problems anyways.

Ickisrulz
01-30-2019, 11:32 PM
Is your shop detached? Are you putting in a subpanel?

You don't typically install a bunch of 240 outlets like you do for 120. You figure out where a tool will be and run wiring to that location (usually) on one breaker. You can size the breaker and wire for more amps that the tool will use. It will cost a little more than necessary.

smoked turkey
01-31-2019, 01:11 AM
If by "shop" you mean a metal working shop which might include a welding circuit, Then you are talking probably 30 amp (#10 awg) and not too much extra cost for a future wire welder. A stick welder would be 40 or 50 amp which is an expensive circuit and would not be, in my opinion, something to pre-wire for until you know where it is to be located. Your runs from the panel should be short with those circuits due to voltage drop being an issue when your amps get large for those machines. In a wood working shop a #12 circuit (20 amps) will work for either a 120v or a 240v circuit depending on how you do the hook-up in the panel. As such the #12 circuits are pretty safe to run in that you have some good options depending on what you decide to do. A large table saw, shaper, or planer can require a 240 volt 30 amp circuit and again you really need to limit the distance from the electrical panel to avoid undesirable voltage drop for those bigger circuits. There is possibly no really good answer to your question without knowing more about your future needs.

Winger Ed.
01-31-2019, 03:16 AM
Its like 120, but you have two of them together, with one neutral & a ground.
Like 120, the max size of the breakers is determined by the guage/size of the wire going out of it from the panel box.

For example: With a 30 amp 220 circuit-- both 'legs' or hot wires, and the 'neutral have to be able to carry 30 amps each.

It's no big deal, but I'd sure read up on it before I started buying stuff and pulling wire.

Lloyd Smale
01-31-2019, 07:27 AM
30 amp circuit will power about anything your going to buy for your garage unless your into some industrial. I would step up to #8 wire though. Especially if the run is a bit long.

StratsMan
01-31-2019, 09:56 AM
Assuming your shop already exists, run the biggest wire you can through the existing conduit. Put a sub-panel in the shop. From there you can choose how to break it out based on the wire size.

I have done this even without putting in a 220v outlet. I like to have 2 legs available so the lights are on a separate leg from the tool outlets. That may be overkill, but it works for me.

Hossfly
01-31-2019, 10:25 AM
Wait till you get the tool and size breaker and wire location for tool requirement. The breaker protects the wire from overload and catching fire.

rr2241tx
01-31-2019, 12:01 PM
Without knowing what your shop is to be used for it is hard to advise you but here is what I did: most serious tools can be wired to run on 240 even if they were running 480 where they were installed new. If at all possible have 240 3 phase run to your main breaker box so your mill, lathe, shaper, etc. will run efficiently. Floor layout was planned for eventual acquisition of the big tools and conduit run to the approximate locations and capped. My welder is on a 240 single phase with a 50A receptacle inside and another receptacle outside for working on big pieces. Benches and work tables are wired with quad 120s every other stud and single 20A 240 on the alternate studs. I prewired the 120 and single phase 240 receptacles with two circuits each on each of the walls. The 3 phase 240s are/will be hardwired as equipment was acquired and run in surface mounted conduit which allows relocation without having to tear out the walls to relocate the service. Another thing, double the amount of lighting you think you need and put work lighting everywhere. You can always turn lights off if they aren't needed but crawling around in the attic trying to add more later is a royal pain in the knees.

jsizemore
01-31-2019, 01:44 PM
Using too big a breaker can cause you not to have the protection it should provide even if it is the correct wire gauge. I had a commercial range hood that wasn't used very often. LRA was 17amps and the circuit was wired for 20 amps. Breaker never tripped. Thank goodness for overload protection in the motor. Residential range hood don't always have that.

David2011
01-31-2019, 03:18 PM
Unless a shop is very small I like to have at least two circuits each for wall outlets and lighting. That assures that there will always be light and power in the event that future electrical work is needed. My last two shops were done that way and I’m about to build another. It will be wired the same, with dedicated circuits for the lathe, mill and welding machine.

rl69
01-31-2019, 07:39 PM
Using too big a breaker can cause you not to have the protection it should provide even if it is the correct wire gauge. I had a commercial range hood that wasn't used very often. LRA was 17amps and the circuit was wired for 20 amps. Breaker never tripped. Thank goodness for overload protection in the motor. Residential range hood don't always have that.
^^^^^^^^this ^^^^^^^

Bigger isn't always better.

chambers
01-31-2019, 09:44 PM
I ran 50 Amp circuit for larger wire welder ( Miller 252), run at least one 30 Amp also for something like a lathe or larger tool. This would be minimum, use mine all the time.

lightman
02-02-2019, 11:48 AM
When I built my house I had plans for a future shop so I buried a 2 inch conduit and a 90 in the slab from under the panel to outside the house. That made the hookup much easier and neater. I ran #2 to the shop and have it on a 100 amp breaker. Thats a little overkill for a one man home shop but I'm retired from the electrical business. I have 2 60 amp 240 volt circuits for a welding machine, one near each door. I have another for my air compressor and another for my table saw. Yes, its 240 volt!

You should draw a sketch and lay out your shop on paper. Walk through it mentally and visualize working it it. Its usually easier and cheaper to do things up front so go ahead and spend a little more than you budgeted for if you can.

Duckiller
02-02-2019, 06:54 PM
$ to 5 years ago I added 200 amp service to my electrical. This let me get central air which is great. 30 amp service for the trailer in the back yard and I put one 220 volt circuit in the garage. Table saw cuts much better and the joiner is only 220.I am seriously thinking about moving. If I do I require a reasonable sized workshop and reloading room. haven't decided size yet but I won't be crowded. 'Workshop will have at least 4 220 volt outlets. Moving extension cords and equipment is a pain.

lylejb
02-03-2019, 12:22 AM
It all depends on what you plan to be doing in the shop. Several of the replies mention 50 or 60 amps, and that's great if you're going to get a welder or other large equipment that needs that much.....and it's a useless expense if you're not.
When I wired my shop, I did much like lightman did, and run a #2 from the main panel and put in a sub panel in the shop. It's on a 100a 240v breaker to the sub panel, and from that I can break out any size or number of circuits I need. In my case, a 20a 240v for the air compressor, 2 120v lights circuits, and 2 20a 120v outlet circuits. If in the future I need more, it's easy to just add a breaker to the sub panel and run the circuit, and not have to pay for and guess where I might need it someday.
There's kind of a sweet spot, price wise, on about that size of panel. I got a square d "kit" at home depot that was a panel and a half dozen breakers for like $50. Hope this helps.