220V 1-phase elec for new shop

[mark mcfarlane]

A few comments.

Thanks Thomas for taking the time to read through this.

As you observed, its an attached building (unless I can't get the easement variances I am requesting ).

re "No inaccessible in-wall wire splices." - I know this is a code violation, but I have an existing outlet circuit that is going to need to be re-routed to accommodate the door into the new shop, and I figured better safe to mention this explicitly than be sorry since in-wall splices seem to be fairly common.

Where we live in Texas, I doubt if there is even any kind of inspection other than the homeowners association making sure I paint the doors the right color, and that the brick matches the existing brick, and that the builders don't chop down the wrong trees (something like a $1,000 fine per tree).

I bumped the spec up to a 200 AMP panel. I need to check what make/model is already in the house, it would be helpful to match that panel. I'm getting on a plane in 6 more hours for the 22 hour flight to Texas, so I can check when I get there (after a coma-like sleep).

You mention that quality 110V outlets can handle #10 wire. I wonder if it makes sense to just run #10 to every wall outlet location and cut the number of outlets in half (one outlet every 5 feet instead of 1-110 and 1-220 every 5 feet) , then I can determine later whether I need 110 or 220 at any given location. The current plan has adjacent 220 and 110 outlets so doing all #10 actually won't require any more wire than already planned, I'd just eliminate the #12 runs. This strategy would require the electrician to either not hook up the outlets to breakers inside the panel, or carefully choose the location of the neutral and ground bus screws for each wire so that there is enough length so the neutral could be swapped, e.g. between the neutral bus and a 220 hot side, and the ground could be moved over to neutral bus (Assuming they are not joined at the remote panel, but are joined at the main house panel). I'm not sure if the electrician would be willing to do this, but it is an interesting concept. I wouldn't want to do a bunch of splices in the panel at a later date, even if it is 'code safe'. Blame it on my anal retentive nature.

re: standard height outlets: I'm currently working under the assumption that I have no clue where the final resting place for everything will be. My current expectation is that the main workbench/assembly table will be in the middle of the room with a 110V floor outlet, and that there will not be a stationary workbench along a wall. Anyway, I can always add a lower outlet pretty easily, snaking down 3' from another outlet isn't a big deal.

Thanks again Thomas.

[mark mcfarlane]

... Something I did in my own shop is also to run the circuits out to a j-box before heading to an actual machine location. That makes it far easier to "relocate" a circuit termination over time, too...

Jim, can you expound on this a little, I'm not sure I am understanding your point.

[mark mcfarlane]

Yes...I do recommend oversize boxes for the 240v outlets and that helps with keeping things tidy. The 10 gage wire is, um...quite stiff. (even 12 gage benefits from the larger boxes)

BTW, I use twist locks for all my 240v circuits. Yes, they are more expensive, but I like the more positive connection

I've spec'd L6-20R and 30R twist locs, thanks.

By oversized boxes, do you mean a 2-gang box with a cover exposing one 'hole' in the middle, or a deeper than normal box,...? Plastic boxes are the norm in my area.

[mark mcfarlane]

Also, add a couple of these in considering how much our phones, tablets, and such have become a part of every aspect of our lives.

http://ecatalog.hubbell-wiring.com/p.../WLFSB002A.pdf

Yep, I've installed those USB outlets before and have a few spares handy. These guys really need deep boxes. I now prefer the surface mount versions for charging areas, such as this one:

[Thomas Bank]

Where we live in Texas, I doubt if there is even any kind of inspection other than the homeowners association making sure I paint the doors the right color, and that the brick matches the existing brick, and that the builders don't chop down the wrong trees (something like a $1,000 fine per tree).

I bumped the spec up to a 200 AMP panel. I need to check what make/model is already in the house, it would be helpful to match that panel. I'm getting on a plane in 6 more hours for the 22 hour flight to Texas, so I can check when I get there (after a coma-like sleep).

You mention that quality 110V outlets can handle #10 wire. I wonder if it makes sense to just run #10 to every wall outlet location and cut the number of outlets in half (one outlet every 5 feet instead of 1-110 and 1-220 every 5 feet) , then I can determine later whether I need 110 or 220 at any given location. The current plan has adjacent 220 and 110 outlets so doing all #10 actually won't require any more wire than already planned, I'd just eliminate the #12 runs. This strategy would require the electrician to either not hook up the outlets to breakers inside the panel, or carefully choose the location of the neutral and ground bus screws for each wire so that there is enough length so the neutral could be swapped, e.g. between the neutral bus and a 220 hot side, and the ground could be moved over to neutral bus (Assuming they are not joined at the remote panel, but are joined at the main house panel). I'm not sure if the electrician would be willing to do this, but it is an interesting concept. I wouldn't want to do a bunch of splices in the panel at a later date, even if it is 'code safe'. Blame it on my anal retentive nature.

re: standard height outlets: I'm currently working under the assumption that I have no clue where the final resting place for everything will be. My current expectation is that the main workbench/assembly table will be in the middle of the room with a 110V floor outlet, and that there will not be a stationary workbench along a wall. Anyway, I can always add a lower outlet pretty easily, snaking down 3' from another outlet isn't a big deal.

Interestingly, Texas has adopted the IRC (International Residential Code) statewide but the IBC (International Building Code) is at a local level. Usually I’ve found them to be more concerned about the public/commercial buildings than the residential, but from the two maps I see more IBC regulation at the local level.



I’m not sure that matching panels has any benefits. It’s not like you’ll be swapping breakers from one to the other. And I certainly wouldn’t go with a lesser quality panel - particularly for a workshop - just to match what you have. I’ve been meaning to upgrade my house panel to a QO, but other chores keep delaying it.

Again, I’m not sure that I’d recommend running 110V/220V to all locations and decide later. That would depend on your wiring diagram as to how many receptacles are on a circuit. Conceivably you could run a 110V and a 220V circuit to each single box and then hook one or the other up to the receptacle or use double gang boxs and then put two 110V, a 110V and a 220V, or two 220V receptacles in the box and connect them to the appropriate wires. But if you only ran one set of wires and then connected them to either a 110V or a 220V breaker, that would take a lot more planning. You may have a circuit going to half a dozen boxes, but only need one 220V receptacle and then have an area with no 110V receptacles.

I’m hoping you’re not thinking of using four wires and a 220V breaker and then “making” 110V receptacles by using only one of the hots...

By oversized boxes, do you mean a 2-gang box with a cover exposing one 'hole' in the middle, or a deeper than normal box,...? Plastic boxes are the norm in my area.

Boxes come in various cable fill volumes - basically, the boxes get deeper while they have the same width and height. You start by adding up the wires and devices (conductor equivalents - wires that start and end in the box -- pigtails aren't counted):

• Each current-carrying wire = 1 cu. in.
• All ground wires together = 1 cu. in.
• All clamps together = 1 cu. in.
• Each receptacle or switch = typically 2 cu. in but some are oversize.

Then you multiply the number of conductor equivalents (total from step one) by their volume factor in cubic inches (listed below)

• 14-ga. wire takes 2 cu. in. per conductor
• 12-ga. wire takes 2.25 cu. in. per conductor
• 10-ga. wire takes 2.5 cu. in. per conductor
• If a box contains different gauges of wire, use actual volume factors for the wires and the largest volume factor for ground wires, devices, and clamps.

From that total, you size your box. For example, single gang boxes come in three sizes, 18 cu. in., 20.4 cu. in. and 22.5 cu. in. You need a box as large or larger than the calculated cable fill.

Yep, I've installed those USB outlets before and have a few spares handy. These guys really need deep boxes. I now prefer the surface mount versions for charging areas, such as this one:

I’ve found that the Leviton ones aren’t much bigger than a standard receptacle. But yes, some of them are huge!

[mark mcfarlane]

And a few pics,... Purple is wood storage, green 'carpet' is a 12' * 19' work area around a slider/combo machine. Wood looking thing is the assembly table/workbench.elec_plan.jpgtop.jpg3D view.jpg

[Steven Wayne]

A few things to add. First, Thomas has given you EXCELLENT advice and he is spot on with all he has said! You can save a ton of money buy buying the locking receptacles and plugs on ebay. I bought boxes of fifty 20A 115V duplex spec grade receptacles on ebay for $60 shipped. These are $6+ ea retail. I use 20A receptacles (fed by 12ga wire) on all of my shop 115v stuff. The spec grade is a much nicer, high quality receptacle. You won't regret installing them. His advice about QO is dead on, too! I bought a new QO panel on ebay for around $100 shipped.

[Robert Engel]

Initial impression reading the post is this is a commercial shop with high end machines.

After looking at the layout, now I'm thinking "How many 5HP machines would someone use in an 800SF hobby shop?

Perhaps if you could specify what machines you are wiring for? #10 wire and 30A breakers are not cheap!

Then again, its none of my business so I probably should delete the post.

[Wayne Jolly]

Anything worth doing is worth over-doing. I read most of this and read nothing about possible future requirements.

Wayne

[Chris Padilla]

I'm with Jim in over-engineering somewhat. If you truly wish to future-proof everything, run 10/3 everywhere. Use the large 4 11/16" x 4 11/16" boxes to deal with the heavier, hard-to-work-with #10 wire (it helps with fill issues), and put in as large a sub-panel as you can stand.

If you really REALLY want to future-proof, put in conduit (flex or EMT) and then you can pull whatever wire you want whenever you want to wherever you want. Again, use the large boxes.

This is what I did for my shop rewire. I ran #10 everywhere through flex conduit and used the large metal boxes (metal is way better...easier to screw in your receptacles). I WAY overdid my utility 120 V circuits by putting them on 4 separate circuits. I should back them off into just one or maybe two...one of these days. All my 240 V circuits are individual. One receptacle per breaker. THAT was probably overkill, too.

You do want some items on dedicated circuits: A/C/Heater; Air Compressor; Dust Collector. These could conceivably all be on at the same time your fire up your table saw so keep those in mind.

Put lights on their own circuit and you'll likely only need a 15 A breaker, #14 wire for that.

[mark mcfarlane]

Initial impression reading the post is this is a commercial shop with high end machines.

After looking at the layout, now I'm thinking "How many 5HP machines would someone use in an 800SF hobby shop?

Perhaps if you could specify what machines you are wiring for? #10 wire and 30A breakers are not cheap!

Then again, its none of my business so I probably should delete the post.

Definitely a hobby shop. 5HP motors will be for saw, shaper, planer, jointer, DC, maybe belt sander,... There may be a combo saw/shaper/j/p due to room constraints (single circuit), or there may be separates. There will be a handful of other 220V machines with <5HP motors (sanders, bandsaw or two,...). I expect I won't know where everything will land in the shop until I am working there for a year or two, so I'm looking for flexibility in machine placement, which is leading to spec'ing '30 Amps of 220 everywhere'.

If I was happy with external mounted conduit, as several have recommended, I could just run my own lines after the build is completed and reconfigure as needed in the future. That's probably the lowest cost, most sensible solution. But I don't want to be looking at external conduit, and having it collect dust, and yada yada yada.

Maybe a raceway near the floor with both conduit and DC piping would meet my aesthetic sense. That's an interesting thought, I don't want to be looking at DC pipes either. I've spent half my adult life living in military-camp grade crap housing (I have external conduit in my current kitchen and living room) and am treating myself to an elegant man cave where I plan to retire, have some fun, and then die, hopefully in that order. So whatever I do doesn't actually have to make sense, it just needs to make me happy.

Yes, my proposed setup may be suffering from design-by-comittee syndrome.

Maybe I'll make my best guess at a few 30 AMP 220V locations, a few 20AMP 220V locators, and wire 110V 'everywhere', and then drop in new 220V circuits when needed. I will have access above the ceiling to add in wall circuits later, I'll just have to deal with the insulation.

Thanks for questioning my sanity, you would probably get along well with my wife.

[Rollie Meyers]

Therein lies the rub, since I don't know exactly what equipment is going into the shop.

It appears everyone is saying 30AMP is enough for a 5HP motor, except for a DC and maybe a large compressor which might need 40 amps on startup.

So it looks like:

1) 5HP = 30A 10ga wire, except for DC @ 40A w/ #8, and 3HP = 20A 12ga wire.
3) L6-20R & L6-30R & is there even a NEMA plug/receptacle for 40 AMPs? I see 30 & 50...
4) No one has a 220V machine that needs the neutral?

220 volts is OBSOLETE in the USA, but in the parts of world where 220 volts is still used it does have a neutral, 30A and larger circuits will have code issues if 120 volts is tapped off those circuits, 208V & 240V motors do not require a neutral.

[Thomas Bank]

Initial impression reading the post is this is a commercial shop with high end machines.

After looking at the layout, now I'm thinking "How many 5HP machines would someone use in an 800SF hobby shop?

Perhaps if you could specify what machines you are wiring for? #10 wire and 30A breakers are not cheap!

Then again, its none of my business so I probably should delete the post.

My personal shop - not commercial - is in the process of getting a 350 s.f. addition to the original 1500 s.f. and has a Syncrowave 250DX TIG welder (110A breaker), Hypertherm PowerMax 1100 plasma cutter (80A breaker), Millermatic 250X MIG welder (50A breaker)… And we go down through the list of air compressor, cabinet saw, 24” drum sander, 24” planer, shaper, jointer…

I have friends with Class-8 tractors to haul their toys - anything from off-road rigs to classic cars to racecars.

I was talking to a guy the other week who built a “T-bucket roadster” (his words) around a 19 liter air cooled V12 Deutz 513 diesel engine. You can find some YouTube videos if you search…

Then again, I’ve heard of people whose “hobbies” are nothing more than walking around a golf course or watching sports on TV with a beer in their hand… I don’t actually know any of those sorts of people personally, but I have to guess they do exist…

[Thomas Bank]

A few things to add. First, Thomas has given you EXCELLENT advice and he is spot on with all he has said!

Thank you. I’ve learned a bit through the years as a registered architect and paying attention to what my electrical engineer consultants are doing and also through building my own shop.

You can save a ton of money buy buying the locking receptacles and plugs on ebay.

Do make sure that you know what you are getting on eBay. There are good deals on overstock or used equipment - and then there is a lot of outright junk whether it is knockoffs or abused equipment.

[Thomas Bank]

220 volts is OBSOLETE in the USA, but in the parts of world where 220 volts is still used it does have a neutral, 30A and larger circuits will have code issues if 120 volts is tapped off those circuits, 208V & 240V motors do not require a neutral.

Ummm… Nothing you’re saying is accurate.

Far from being obsolete, single phase 220V power is used throughout the USA. Unless you’re making the argument of the designation of 220V as opposed to 230V or 240V or such. Currently power is standardized at 120V and 240V (−5% to +5%). So you can have voltage readings of about 114V to 126V and 228V to 252V. However, the historical standardized numbers were 110V and 220V, so a lot of people still use those to refer to those. I’ve personally seen voltages below 110V in rural areas even today - which tends to play havoc with things. I also know (architectural) electrical engineers that still refer to 110V and 220V - catsup/ketchup.

Outside the USA, 220V is a completely different animal. In the USA 220V (single phase) is achieved by two hot legs being 110 volts and 180 degrees apart each while 110V power is achieved by one 110V hot leg to neutral. “European” 220V is achieved like our 110V is here - each hot leg is 220V and 180 degrees apart and you use one hot leg to neutral for most household appliances. Trying to compare “US” 220V power to “European” 220V power will likely get you into trouble.

I’m not sure what code issues you refer to for 30A and larger circuits - 120V 30A and 50A circuits are commonplace. Beyond that manufacturers tend to just switch over to 220V because the amperage is halved and therefore requires smaller components. Many motors can be wired to run at either 110V or 220V, but (for example) a 60A 110V motor will only take 30A at 220V (Ohm’s Law).

Finally, you’re comparing apples and oranges. While 240V can be single-phase or 3-phase, 208V refers to a 3-phase setup. Three phase has a central neutral with three legs set evenly apart. For 208V 3-phase, you’re using two legs 120 degrees apart. But 3-phase power - like “European” power - is a completely different animal and a whole ‘nuther discussion.