# Shop wiring



## welcon (Dec 3, 2012)

Trying to get a few tips for wiring my shop. I have been thinking of running my 15 amp 14/2 circuits inside the wall and running my heavier circuits in EMT on the outside of the wall. Most of my larger tools are wired for 220, those tools being a table saw, jointer, thickness planer, 1 1/4 production shaper, 17" band saw, 6' x 108' sander,
24" double drum sander and a compressor. I am not to sure if I really need a separate circuit for each one, or if I should run maybe three circuits as most of those tools are mounted on wheels anyway and can be moved easily.

I was also thinking about having my receptacle box's around 4 feet of the ground. Nothing worse than bending over all the time to plug things in, especially if you have a mess and need to move things around to plug stuff in.
I also have a drill press and scroll saw which are wired 110 and they should probably get their own 15 amp circuit, maybe increasing the wire size to 12/2.

Any way any suggestions would be greatly appreciated.


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## toolie (Mar 16, 2011)

more outlets are always better than less. minimum two 220v 20a circuits, lights on at least one, preferably two, 15a circuits and at least two 20a general purpose circuits.


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## EEngineer (Jul 4, 2008)

I'd recommend the sockets be a little higher than 4'. That way you can lean a 4X8 sheet against the wall and still reach the socket.

The only 15A 110V circuits in my shop are for lights. Everything else is 20A. Run 12 AWG everywhere - upgrades are easy and it keeps the resistance down for very little difference in cost.

NEC requires GFI on every circuit. I found GFI sockets to be cheaper (way cheaper!) than GFI breakers on 110.

If you have a detached shop pay particular attention to the NEC rules for grounding.


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## HorizontalMike (Jun 3, 2010)

IMO, if you are in fact installing new wiring *inside the wall*, forget about using 14/2 wiring(way too small). Go with 12/2 as a minimum. You usually only get one chance when initially wiring inside the wall, so make the most of it and you will not regret it in the future.

Also, 4ft is a good height for receptacles ** Suggest 4-gang boxes every 5ft (or at least 6-8ft) apart. I originally wired my metal building/shop only at the major pillars about 15ft apart, and had to retrofit several more receptacles at half that spacing when I discovered just how much I needed them. You really do need closely spaced receptacles.

If you CAN run separate 240v circuits for EACH machine, so much the better. It sure makes identifying them easier at the power panel. I used a 125amp power box, but now wished I had gone with another 200amp panel like at the house main feed. You cannot go wrong with more room at the power panel. Bigger boxes do not cost that much more and the return on convenience is priceless, IMO.


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## pmayer (Jan 3, 2010)

I would run everything inside the wall. Separate circuits for each 220 tool. All 12 ga. wiring for your 110 outlets, 14 ga. for lights. I would also suggest running a dedicated 110 outlet on each wall that can be converted to 220 by just swapping a breaker if you ever want to. This is handy and I have taken advantage of this in my shop. I ran 110 outlets on every third stud which has worked out well. I put a separate circuit on each wall which is overkill for sure, but I do sometimes share my shop with my father so it is conceivable that we would overload a circuit but not very likely since all of my stationary tools are on dedicated 220 circuits. Its also nice to have an outlet in the ceiling over my assembly table, where I have a retractable extension cord. I use that thing all the time.


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## REO (Sep 20, 2012)

As EE suggests go a little higher than 48" for the random sheet of material leaned against the wall. if you are working alone typically there is certainly no need to run individual circuits for each machine. In my shop I ran individuals for air compressor, DC and a welder outlet. the rest are split between two 220 20A circuits and the 110V is piggybacked on those so there are only two runs of wire for general outlets. I run a 7.5 HP RPC which is also wired in the walls permanently but unplugs so I can take it with me if needed elsewhere. Many of y tools are in rolling nests. TS, Router table, Planer, 6×48 sander on a lift. DP, Shaper, BS. I bring 220 to the "nest" on 10/4 from the wall and have 110v outlets mounted all round for power tool use at the "nest" For the 220v I used 12/3 WG, the 3 PH is run with 10/4, and the welder with 6/4. All 110 outlets are required to be tamper resistant as well. in my situation I couldn't "daisy chain" the GFI's either


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## BBF (May 13, 2013)

Take HorizontalMike's advise when you think that you have enough outlets then it is time to double them. Extension cords are not the way to run a shop. 14-2 should be used only for lights and not on a circuit with any tool on it, you don't want the lights going out when you are in the middle of cutting something.


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## macatlin1 (May 5, 2010)

For my shop I put 220VAC outlets on the East and West walls located 12 inches above the floor. Each wall was on a separate circuit. For the 110VAC outlets I put separate circuits for the East, West and North walls. On the East and West walls the outlets were mounted at 54 inches to avoid having to bend down and get behind the equipment and to allow leaning 48 inch wide stock to lean against the wall without interfering with the outlets. On the East wall I also installed a separate single dedicated outlet (switched) for the dust collector. By going with a dedicated outlet there is no need for GFI. The switch allows me to turn on the DC without having to reach around behind it. I did buy a 20A switch. The DC circuit also powers the light over the man door on the outside. The outlets along the North wall are at conventional height as having equipment or storage along this wall will interfere with access to the house. All 110VAC strings are started with a GFI outlet. I also have an "office" alcove with it's own GFI protected circuit which was part of the original house/carport/garage/shop circuit. The lighting in the shop is 20A with 2 strings of 6 dual tube 4' fluorescent light fixtures and 6 can lights where the fluorescent fixtures would interfere with the garage doors. Each string is controlled by a separate switch. I retained the original garage light and turn it on if I am working at night just in case the lighting circuit fails. I wouldn't want to be left in the dark with running machines. I also added a separate airconditioner circuit with a dedicated outlet. The AC and outlet are mounted through the wall and near the ceiling. I also replaced the duplex outlets the garage door openers were plugged into with single outlets so they became dedicated and not requiring GFI's. I had no problem with the inspector and even though I did the work myself he was impressed.


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## Grandpa (Jan 28, 2011)

I put 220V where needed and sized as needed. I used 110V 20A for everything else. Also look for 20A receptacles. Most are 15A. make everything heavier than required today. I place my receptacles at 5 ft because U have a metal building and there is a horizontal member there. Got luck I guess. GFCI everything on 110VI have receptacles every 5 ft horizontally too. All around then some in the floor.


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## teejk (Jan 19, 2011)

If you are going to hide the wiring behind walls, figure out your interior finishing material so cutting in the outlet boxes hits an edge. Faster than trying to cut boxes into the middle of a large panel. I personally like the looks of EMT external conduit and since I am always hanging stuff I always know where the wires are. They are a bit of a dust collector though.


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## SeattleD (Jun 22, 2013)

I'm facing a similar challenge, compounded by being a "renter". My place, built in 2007, has a ~540 sq' garage, with ONE 15 amp 120 volt outlet, fed by 14 ga. A major limitation. It's hard for me to believe this is even up to code, but given the relative newness of the place, it probably is. And since I am renting, I'm limited in what I can do to address the situation.


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## Knothead62 (Apr 17, 2010)

If I recall my training at Lowe's to work in the electrical department, you are only required to have the first outlet on the line as a GFCI. The rest "downstream" can be regular outlets and the GFCI will trip when needed. Has this changed? Would like clarification. Thanks.


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## KentInOttawa (Jun 25, 2013)

I strongly agree with the boxes mounted a little over 4', and with mounting as many as you can. Because workshops can, and should, be dynamic spaces that adapt as we do, I recommend that all wiring be surface mounted so that changes are considerably easier.

In a past shop, I had a master shut-off switch at the door and 2 sub-panels. The one was a small panel and the only circuit on it was for the lights and the air filter. The second sub-panel had it's own shut-off switch and everything else. I plugged an old radio into one of the 115V circuits on the second panel, mounted the radio where I couldn't reach it, and then turned it on to a local radio station. Then, whenever I heard the radio, I knew that my tools were live and extra caution was taken. If I wanted to change a blade or make any other potentially dangerous changes, I would shut off the master switch on the second panel. Hearing the radio was also a cue to me to turn off the tools master shut-off when I closed up the shop. As a bonus, it would be impossible to trip a breaker with a tool and be stuck in the dark with a spinning blade. It worked well for me and it will also be done in my new shop (summer 2014)


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## smitdog (Aug 20, 2012)

Knothead, that's what I had learned and the instructions that came in the box of GFIs I got confirmed - you only need a GFI outlet at the beginning of a circuit to protect the whole line, but only if wired correctly! A single line must feed the GFI's input terminals and then the wiring must come out of the exit terminals so that the GFI breaks the line. If you try to pigtail the outlet or branch off at a junction box before the outlet you will bypass the GFI's ability to break the connection. So everything in front of the GFI is not protected but everything coming out of the GFI box IS. I GFI protected my whole kitchen (10 outlets or so, can't remember) on 2 separate 20A breakers and only used 2 GFI outlets.

I tested each outlet in the string and they all worked just fine.


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## jimmyb (Mar 21, 2013)

As an ex IBEW electrician, my two cents. You do NOT need a seperate circuit for every 220v machine unless you plan on running them all at the same time.

Knothead62 is correct with GFCI outlet. First outlet then control the next 5(?) outlets wired after it.

I long the taller than 48" height for reasons stated . Switches are mounted at 52" to top of box and would then be a good height for all.


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## shawnmasterson (Jan 24, 2013)

I agree with sharing 220 circuits. the only advice I have for sharing is to plan out the locations and size of the machines. 
My shop has 3 - 220 circuits
1 - 30 amps - TS 3Hp and not in use right now but was for the old planer 5 Hp
2 - 30 amps - compressor 5 HP and DC 3Hp
3 - 50 amps - RPC 10 Hp (for the new planer) and welder
as for 110 each wall has a 20 amp circuit for recepts and a dedicated circuit for lights.


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## crank49 (Apr 7, 2010)

As almost everyone else has said, 14ga only for lights. Outlets just over 48" above the floor.

My copy of the NEC is slightly dated, 2010, but it calls for a separate circuit for each 220V load unless each load has it's own disconnect and overload protection.

I found it a good idea to have duplex outlets. In fact, I put 4 outlet circuits in my shop, and kitchen as well, and no two adjacent outlets share the came circuit. If I have 4 outlets in a row there are 4 different breakers protecting them. The power cord reel in the ceiling is a great thing to have as well.


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## Holbs (Nov 4, 2012)

I just installed subpanel and circuits in my garage. See my blog for things I encountered.
Everything was run thru studs. 
I installed my outlets 52" high (4" cushion from 4×8 boards).
I installed a GFCI outlet in middle of ceiling for… future.
All 110v outlets use 12/2 romex with 20amp outlets.
I ran 10/3 (it would of been more logical to run just 10/2) for my 220v 30amp outlets.
Consider future addons you would like to use and run wire: ceiling mounted air cleaner, Reznor gas heater, drop lights, ceiling fan, 2 zone lighting (would suck to blow the only zone lighting fuse with a 3000+ RPM saw blade 1" from your hands).

If you run even a single circuit, by code you must get city permit. If house burns down because of faulty wiring, insurance folks will just say 'tsk tsk sorry'. Also, if you re-sell the house and someone finds out you added a circuit, the city will come after you with fines or such if no permit was ever issued.


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## Grandpa (Jan 28, 2011)

I didn't mention it earlier but I ran a second circuit for a 4 bulb fluorescent fixture. The only light with its own circuit. I just didn't want ALL the lights to go off because I didn't put in any windows. It gets dark in there even in the daytime.


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## kizerpea (Dec 2, 2011)

My hole shop is 12/2 ..plugs are 53in from the floor an 58in apart ..220 plugs are 10ft apart..so if I need to re arange my tools there are plugs there. dceated line to the dust collector..also have cords droped from the ceiling around where my assembly table is…plugs are just over head high to me…I hate cords on the floor.


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## benchbuilder (Sep 10, 2011)

Best to call a real electrician and get his advice, and plck up a copy of your local codes. Your insurance will most likly not pay if you have a fire or storm damages if its not wired to code… just my thoughts..


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## welcon (Dec 3, 2012)

Thanks for all the info and advice guy's. Just went to our local wholesaler and loaded up, let the fun begin. As a home owner in British Columbia we may pull our own electrical permit, the rough in is inspected and also the final. I would never rewire a new or existing shop without taking a permit first just in case of fire and insurance reasons.


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