Electrical layout for new shop

[cody michael]

I am building a polebarn and I am putting a 20x30 room in for my wood shop, I am trying to decide how to run 220 outlets, I currently have a dust collector, tablesaw, bandsaw, drill press, radial arm saw, and Vertical Mill that all use 220. I am trying to decide how to layout outlet locations. My old shop had all designated outlets for each machine, however I am not sure if that makes sense with my new bigger shop, I am also unsure of layout right now. since I never run more the the dust collector and 1 other machine I am considering putting in like 4 circuits one for each corner. and a designated outlet for dust collector. I would put in outlets like every 6ft to make sure I can move machines around until I find a layout I like.

Any advice on the layout? my old smaller shop I ran the planer out the back door and I think I will keep that concept here (when its warm out) so the planer will be on the top right in the picture. any advice on dust collector placement? I normally use the dust collector on the tablesaw, jointer and planer, I am thinking maybe put the dust collector on the right wall put tablesaw in center and jointer planer can both run out the door for long pieces on top right. However I am open to ideas.

[George Yetka]

I would layout your equipment on paper and figure out makes sense for that. Once you know where the machines will be run power to those spots. Figure on possibly rewiring at some point. Be able to adapt. If you are on slab you may want to think about adding a few boxes in the floor, even if they stay empty. For stuff on the outer wall you can always easily add it later.

[Jim Becker]

My lessons learned from the old shop include "you can share a circuit for many machines that never will be used at the same time"...use the highest amperage requirement for such a shared circuit, such as 30 amps which is typically needed for machinery that pushes 5 amps, give or take. Use dedicated circuits for machines with special needs or that need to operate simultaneously with other machines. (DC, Compressor, HVAC, etc) Embrace use of pigtails on the machinery so changing locations only means making up a new extension of proper length, which is easier than moving an outlet and related to that, put the machine circuits in surface mount conduit or raceway so that you CAN easily move them if required.

For a specific layout...that's really impossible to give you advise on here because until you decide where machines need to live to support your personal workflow, any specific input would be speculative. Make a scale diagram of the intended shop space and scaled cutouts of the machines and their infeed/outfeed requirements. Play with that on the table and come up with one or more alternatives. That's only a baseline, however, until you have the actual machines sitting there so you can make a "final" decision for the initial setup. You can start planning your conduit/raceway from there, including potential ceiling drops. One you have machines in place, moved around ten billion times and generally in place, you can then do your final wiring and terminations.

[Scott T Smith]

Cody, in my shop I ran 3" pvc conduit under the slab from the load centers to each wall. In the wall I transition to a horizontal run of 2" conduit that has several junction boxes in it. This allows me to pull wires to any wall location in the shop at any time, providing a lot of flexibility with future wiring.

Additionally, as needed I run wiring to outlets in the ceiling that I've placed above the corners of some of my equipment, and I use twist-lock extension cords to run power from the ceiling outlet down to the equipment.

My four load centers (two 240 single phase, one 240 three phase and one 480 three phase) are all connected underneath by a run of 6" rectangular conduit. The 3" conduits that run under the floor all terminate into the 6" rectangular, allowing me to run wiring from any load center through any conduit.

Best of success to you with your new shop.

Scott

[Andrew Seemann]

I'm 24 x 28, so roughly the same size. I ran individual 240V to all the machines (DC, compressor, bandsaw, tablesaw, jointer, planer). I ran a 240V to each wall where I knew I was likely to put a machine, 3 circuits to ceiling mounted twist locks, and then lines to where I knew I was going to put the DC and compressor. I ran four 120V lines with color coded outlets for machinery to roughly each wall (the long wall with the row of machines has two, and the hand tool ell has only one). The fridge, AC, lights, heat, etc have their own circuits.

One thing that I did, having seen this in a TV studio shop, is put in a sub panel off the main sub panel that I could turn off with a single breaker in the main panel, which drops the power to all the 240V machines and all but one of the 120V tool circuits. The inspector looked at it kind of askance when he first saw it, but when I explained that I had small kids and it killed the power to everything sharp, he liked the idea.

I realize that my wiring layout is probably overkill, and then some, but I did it all myself, and I kind of get into that sort of thing

[cody michael]

I'm 24 x 28, so roughly the same size. I ran individual 240V to all the machines (DC, compressor, bandsaw, tablesaw, jointer, planer). I ran a 240V to each wall where I knew I was likely to put a machine, 3 circuits to ceiling mounted twist locks, and then lines to where I knew I was going to put the DC and compressor. I ran four 120V lines with color coded outlets for machinery to roughly each wall (the long wall with the row of machines has two, and the hand tool ell has only one). The fridge, AC, lights, heat, etc have their own circuits.

One thing that I did, having seen this in a TV studio shop, is put in a sub panel off the main sub panel that I could turn off with a single breaker in the main panel, which drops the power to all the 240V machines and all but one of the 120V tool circuits. The inspector looked at it kind of askance when he first saw it, but when I explained that I had small kids and it killed the power to everything sharp, he liked the idea.

I realize that my wiring layout is probably overkill, and then some, but I did it all myself, and I kind of get into that sort of thing

I will have the a subpanel just for the wood shop, I will run the light circuit to the main panel that way I can work on electrical without being in the dark.

[Andrew Seemann]

Warning: Completely unsolicited advice follows

If you have the option, I highly recommend running everything in surface mounted conduit, even the lights (which I ended up having to move one of in my current shop due to an unanticipated dust collection pipe). That way you can easily add, modify, or remove anything from the system. I did my first workshop with Romex in the walls, and very quickly regretted it. It seemed like right away there were a few places where I desperately wished the outlets were a few inches to the left, or that I had put another in, or that I had run 240V rather than 120V, etc.

[Jack Frederick]

My lack of organization is stunning. Couple that with not knowing exactly what machines would reside in the 30x30 place I put 4-50 amp outlets by the doors to serve the welder. The 30A were placed around the shop on the blank walls at 52”. I have my machines on rolling bases so this works out. I went another way with my shop from Andrew. My electrical is down fed out of the attic area. On my 10’ walls I set 1/2” plywood vertically. I can access any part of the wall interiors in minutes and then replace it if I change something. So far in 7 yrs I’ve only been in once for the solar wiring to the panel, but it took me 15 minutes to open the wall and about 10 to replace it once the work was done. No surface conduit. 110v outlets were set alternating at 16” & 48” every 3-4’ depending upon window and door location. If I cover a low receptacle there will be one close-by at 48.” Taht has worked out well for me

[Clifford McGuire]

I turned a basement rec room into a shop. While it was empty, I had the electrician:

- put a subpanel in the adjoining utility room
- Put a 220V 40A outlet on either side (I'm pretty sure where my table saw will be going, but it's nice to have the option to move it.)
- A dedicated 220V 20A for the Dust collector
- A dedicated 110V 15A for the drill press & router table

- And then four 220V 20A outlets scattered around the room. Those are on the same circuit.

There's room for a few more circuits in the panel.

PXL_20210921_121128425.jpg

[Charlie Velasquez]

I will have the a subpanel just for the wood shop, I will run the light circuit to the main panel that way I can work on electrical without being in the dark.

Not if your work will be inspected. Only allowed to run one power source to your pole barn except for specific applications (fire alarm, fire suppresion, well pump come to mind. General lighting is not one of those applications). Remember, you will need a disconnect at your subpanel that will shut down ALL power in your polebarn (combination 2017 and 2020 - for first responders). You could run power to your subpanel, then run a three-way switch from that power source with one switch back in the house, (I have that in my workshop so I can control an exterior light and a switched outlet for an electric heater) but it needs to be sourced from the subpanel.

But not really an issue any longer. For a few bucks you can buy some very bright battery LED worklights.
I have a couple of LED camp laterns I use.
In my house I have an LED emergency light at our stairwell and at our electrical panel. Smart charging so it's always charged, and comes on automatically when the power goes off.

Edit: Uhhhh, ignore this if your plan is to have a woodshop sub panel from your polebarn subpanel in the same building. When you used the word main I assumed you were speaking of your main in the house, or on a pole. Or, if your polebarn has its own meter and main, this is not an issuse.

[Leigh Betsch]

I just put a 110 and 220 single phase outlet side by side about every 8 ft around the perimeter. These will be on 3, 110 20 amp and 3, 220 20 amp circuits. I will have all my large 3 phase and 220 high amp machines on ceiling drops above each machine. The dust collector, phase converter, and air compressor are on dedicated circuits in the attic. I likely have too many single phase outlets but I'm sure it was way more cost effective than surface mounting everything in conduit. And the outlets are now there and I shouldn't ever have to add more. In my old shop I did surface mount all the electrical in conduit. But I didn't like it. I didn't like the look and I didn't like the horizontal runs collecting dust. Working in ISO cleanrooms I learned that horizontal surfaces are the enemy of good cleanroom design. So I'm applying some of the same concepts in my shop.

[Jim Becker]

Charlie, as you note at the end of your post, I've seen installations like Cody describes that have a few circuits for lighting and maybe HVAC that are pin the primary panel for the outbuilding and machine circuits in a separate subpanel south of that so all the machine circuits can be killed with one breaker while keeping the lights on. There are even meter boxes that have space for a few primary circuits. This wouldn't violate the "one source of power to the building thing". I'm actually considering doing this when I get to my own shop building project next year. My temporary shop already emulates that because the subpanel I installed only has machine circuits in it. Lighting is off the main panel and existing circuits. With a flip of one breaker, I can kill all the toys.

[Andrew Seemann]

With a flip of one breaker, I can kill all the toys.

It is very comforting to be able to leave the shop and know that everything is off except the lights and heat (I'm thinking of you, Mr. Compressor). And that they can only be turned on by someone who knows what they are doing

[Jim Becker]

Andrew, that's very true for many folks, especially if there are kids in the house. For myself I'm not concerned with that; rather, I want to be able to work on and change things around when necessary and being able to essentially lock out a whole panel meets that need. For the relatively low cost of a subpanel, it makes sense to me as a good solution for safety.

[Randall J Cox]

Like Jim B said earlier, I recently ran 240 to my shop and machines share 5 each 20 amp breakers. Only one circuit has two machines running on it at once, the dust control system and the radial arm saw. Combined, comfortably under the 20 amp breaker and one of the least used machines (RAS) in my shop. One of the circuits is dedicated to my new 240V mini split which wants 15 amps all to itself. Also, even though I have 125v outlets all over the place in the walls, I added two boxes (four plugs per box) on two 20 amp circuits just for good measure. Randy