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Forum topic by weathersfuori posted 12-19-2016 03:45 PM 1044 views 1 time favorited 40 replies Add to Favorites Watch
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weathersfuori

86 posts in 970 days


12-19-2016 03:45 PM

Topic tags/keywords: electrical wiring shop layout shop design

Hi Everyone,

I’ve read through several topics like this and they have been very helpful in generating ideas for my own situation, which I am sure many of you have been in as well. I am mostly a hobbyist though I do sell a few things to fund my hobby. My little shop has come a lot farther than I ever expected it to, and I’m ready to take it up another notch with an upgraded 3HP table saw. More than likely, this will be the last major upgrade to my equipment as anything more than I have could only be justified by additional time spent in the shop making things, and with 3 young kids, I’m already pushing those boundaries.

So, in order to upgrade my saw, I’ve got to add 240V service to my detached garage. Fortunately, it is unfinished and the main panel is right in the middle of the wall where all my bigger machines are located. My shop is small, essentially just a single stall in the garage with a couple feet of extra width. I need to add a sub panel, as my main panel is already out of space, but the sub panel will be located right next to the main. I am going to resist the temptation to install the sub panel myself since I have very little experience with electrical, and while I feel I’m pretty handy, I want to make sure this is done correctly. That said, the cheaper I can make this, the sooner I can get my new TS and maybe even add some extras to it, so I am looking to find ways to save on the wiring and may consider installing receptacles myself.

I wanted to run this past the group to make sure I’m at least in the ballpark on what I need so that I can provide an electrician with enough detail to make this process go smoothly, and also so that I don’t sound dumb enough to be taken advantage of (no small task!).

Since all my tools currently run on a 20A, 120V circuit and meet my needs that way, the only thing that I HAVE to have on 240 is the new TS, but I figure it would be best to add a second 240V circuit to the new sub panel now for future use if I ever decide to upgrade my dust collector. Realistically, I probably won’t, but the extra 240V circuit seems to be a smart move just in case, and I assume this won’t add much to the total cost in the end. 20A enough for these two circuits?

Aside from the two 240V circuits, I don’t think I need more than two additional 120V circuits… I never run more than 2 tools at once currently (TS+DC, BS+DC, planer +DC, jointer+DC, etc), but could see adding a hanging shop filter sometime soon, which is probably best on its own circuit. The remaining circuit would be used for smaller tools and/or the planer, jointer or band saw. I may decide down the road to upgrade my band saw and/or jointer to 240, but could always run them on the same circuit as the table saw (not at the same time).

My lighting is minimal and although I may add additional florescent fixtures down the road, they are currently covered by a circuit on my main panel, so nothing additional is needed at this time for lighting. All my machines are on wheels, so I don’t need a bunch of receptacles. I’m really just looking to keep this as minimal as possible, since the only real reason for rewiring is the new table saw, but obviously I’m not going to add a subpanel with just one 240V circuit and call it a day. Given the above info, what size/amperage sub panel should I be asking for?

My dad is retiring next month and my old hobby, fishing with him, may take over before too long so I don’t want to go overboard with shop set up, especially given how small my shop is.

Any thoughts/advice is greatly appreciated!

-- Weathersfuori, Texas, www.facebook.com/f5creations


40 replies so far

View rwe2156's profile

rwe2156

2717 posts in 1321 days


#1 posted 12-19-2016 04:04 PM

I think you’re on the right track.

I would suggest a couple 120 circuits for a couple reasons. For example, if I plug my shop vac and miter saw in same outlet, about 50% of the time it will pop as soon as the saw starts.

Also, if you keep the lighting on one circuit, if any tool ever blows a breaker you won’t be in the dark.

Its very easy and cheap to do even in a small shop.

-- Everything is a prototype thats why its one of a kind!!

View HorizontalMike's profile

HorizontalMike

7665 posts in 2754 days


#2 posted 12-19-2016 04:23 PM

I would recommend putting in at least a 100-125amp panel/box. Even though right now you think you will never need to add breakers/240v/outlets/etc. protect yourself and just do it. This way you will never have to come back and “re-do” it if and when you want/need a new WW toy. The difference in cost is minimal and you will thank yourself many times over. Just my 2-cents…

-- HorizontalMike -- "Woodpeckers understand..."

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weathersfuori

86 posts in 970 days


#3 posted 12-19-2016 05:06 PM

Thanks guys. Mike- I hear ya and totally expected this response. Do you think this would work for me?

The 240V circuits will each take up a space right? I know (or think I know) you can fit two 120v breakers in a space provided they are 20A or less. If I install two 240V circuits and two 120V circuits, that should leave me with at least 3 open spaces for future expansion, right?

EDIT: Don’t know what I was thinking with this second statement. Obviously only one breaker will fit in a space… So these panels are advertised as having capacity of twice as many circuits as there are spaces… so you can have two circuits on a single breaker? Apologize if this is a stupid question, but I don’t really understand that part.

Anyhow upon further review, it seems I’ll use up two spaces for each 240V breaker. Can I run two separate 240V circuits off that one 240V breaker? Or am I going to use up 4 spaces with two 240V circuits?

-- Weathersfuori, Texas, www.facebook.com/f5creations

View WhyMe's profile

WhyMe

910 posts in 1401 days


#4 posted 12-19-2016 06:18 PM

First things first, what size is the existing panel in the detached garage and does it have a main breaker or is there a main disconnect at the detached garage? A double pole breaker will use 2 spaces. The panel you linked to can use twin/tandem breakers so that is why it show 12 circuits. Using two double pole 240V breakers(4 spaces) and one 120V tandem(1 space) for two 120V circuits will leave one space open for another 120V tandem or two 120V circuits.

View weathersfuori's profile

weathersfuori

86 posts in 970 days


#5 posted 12-19-2016 06:50 PM

WhyMe- thanks! Your explanation is very helpful and it all makes perfect sense now. The existing panel does have a main breaker. I know that much. It supplies all the power to our home. I’m not 100% certain what size it is but I think it is a 200A main. Will check it out in a couple hours when I get home and report back. The house is only 10 years old, so we aren’t dealing with a real old setup.

I’ve ruled out the panel I linked, as I want a little more wiggle room for expansion than that. I’m thinking this would be a better option and only costs about $8-10 more. Just trying to get an idea of what the itemized cost will be for this project, with the wildcard being labor for the electrician, and maybe I can save some $ by buying the supplies myself.

-- Weathersfuori, Texas, www.facebook.com/f5creations

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WhyMe

910 posts in 1401 days


#6 posted 12-19-2016 07:45 PM

The reason I asked about the existing panel and main disconnect is if the existing panel was a main lug with no main breaker and only had six breakers by adding another panel you’d exceed the number of breakers you can have without a main disconnect in the detached garage which would require a main disconnect to be installed at the detached garage. But since your existing panel is a main breaker all of that doesn’t matter. I didn’t see a link to your new choice of a panel, but at least do a 100 or125A with 20 spaces or 12 spaces/24 circuits.

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weathersfuori

86 posts in 970 days


#7 posted 12-19-2016 08:32 PM

WhyMe- Gotcha. I thought that may be the case.

Oops! Here is the link to the other panel... which looks like a match to your recommendation. From what I’m hearing so far this should be a little more than enough for what I need now, and enough for what I believe I’ll need in the future.

-- Weathersfuori, Texas, www.facebook.com/f5creations

View bonesbr549's profile

bonesbr549

1445 posts in 2907 days


#8 posted 12-19-2016 08:46 PM

I’ve done 5 shops now from tiny sub panel to my current full panel. Like you I have one 220 for my DC, and one for my tools, as I’d never run more than one at a time.

I have seperate 20A circuits for my other tools. Finally I’d recommend not sharing your lights with your tools. I had to do that once not good. I even have my lights on two sep circuits. Worst thing I ever had happen was my ligh breaker tripped and I was in a dark room with a saw running. That will take your pucker level off the charts

:)

Good luck.

-- Sooner or later Liberals run out of other people's money.

View HorizontalMike's profile

HorizontalMike

7665 posts in 2754 days


#9 posted 12-19-2016 08:52 PM



Thanks guys. Mike- I hear ya and totally expected this response. Do you think this would work for me?
The 240V circuits will each take up a space right? I know (or think I know) you can fit two 120v breakers in a space provided they are 20A or less. If I install two 240V circuits and two 120V circuits, that should leave me with at least 3 open spaces for future expansion, right?
EDIT: Don t know what I was thinking with this second statement. Obviously only one breaker will fit in a space… So these panels are advertised as having capacity of twice as many circuits as there are spaces… so you can have two circuits on a single breaker? Apologize if this is a stupid question, but I don t really understand that part.
Anyhow upon further review, it seems I ll use up two spaces for each 240V breaker. Can I run two separate 240V circuits off that one 240V breaker? Or am I going to use up 4 spaces with two 240V circuits?
- weathersfuori

Looks like that will work well. FWIW, each “space” is a full height two-pole space good for 240v. For 120v you fit in “half height” single-pole breakers (two in each “space).

Here is mine below. I went with a 125amp box and have three 240v circuits and six 120v circuits set up for my shop. I went with GE brand because that is what my main panel is. I have a 100amp breaker on my main panel, that feeds the sub-panel. Since my sub-panel is in a metal building, I surface mounted the box on one of the beams.


PowerMark Gold 125 Amp 6-Space 12-Circuit Outdoor Main Lug Circuit Breaker Panel $40.25

GE

http://www.homedepot.com/p/GE-PowerMark-Gold-125-Amp-6-Space-12-Circuit-Outdoor-Main-Lug-Circuit-Breaker-Panel-TLM612RCUP/100168646

-- HorizontalMike -- "Woodpeckers understand..."

View Fred Hargis's profile

Fred Hargis

4769 posts in 2333 days


#10 posted 12-19-2016 09:04 PM

When you look for the new panel, instead of buying on price you might want to get one that matches the existing unit…that’s probably a Square D QO, but there are quite a few others. Since the panels will be so close together, the new panel (and breakers) will be about the only costs for parts, the piece of wire will only be a few feet long. Anyway, having them match will give you the ability to swap breakers around if that’s ever needed for some reason.

-- Our village hasn't lost it's idiot, he was elected to congress.

View weathersfuori's profile

weathersfuori

86 posts in 970 days


#11 posted 12-19-2016 11:44 PM

Great advice here guys, much appreciated. Good point on getting the same brand. I’m thinking I will have to move a couple existing breakers over to the new panel to make room for the panel feed, since my main panel is maxed out.

HorizontalMike… so a 240V breaker will only take up one space in the new panel? So if I got a 6-space panel, installed two 240v breakers, I’d have 4 spaces left which could accommodate 8 120v breakers or an extra 240 and 3 120s? That’s your setup, right? This seems to contradict what was said earlier about dual pole breakers and how much space they take… but since you actually have the setup, thought I’d ask! For $5-10 more, I might just go for the 12 spacer anyway, but was just curious.

-- Weathersfuori, Texas, www.facebook.com/f5creations

View WhyMe's profile

WhyMe

910 posts in 1401 days


#12 posted 12-20-2016 12:58 AM

HorizontalMike has a GE panel and breakers. Square D is different and 2 pole breakers use 2 spaces. The tandem single pole uses 1 space. There is a Square D Quad Tandem that is 1 DP plus 2 SP that uses 2 spaces. If you use a Square D panel you can’t go by what HorizontalMike said for his GE panel.

Edit: The Quad is only for the Square-D Homeline. I don’t think there is a Quad for the QO.

View weathersfuori's profile

weathersfuori

86 posts in 970 days


#13 posted 12-20-2016 01:34 AM

Gotcha… I figured you were both right!

Turns out I have a Cutler Hammer main panel. I noticed there are some Square-D breakers in it that were added by a previous owner when they put the pool in. I’ll get a Cutler Hammer sub since, looking my panel again, I’m going to have to do quite a bit of rearranging in order to make room for the feed breaker for subpanel. I’ve attached my main panel here… any advice on what to take out here and move to the subpanel? Ugh…

PS. Main breaker is 150A… does that change anything for my subpanel?

-- Weathersfuori, Texas, www.facebook.com/f5creations

View WhyMe's profile

WhyMe

910 posts in 1401 days


#14 posted 12-20-2016 01:46 AM

That is a BR line of Cutler-Hammer. Square-D breakers are a no no in a CH panel. They fit but are not listed for use in the CH panel.

View Roy Turbett's profile

Roy Turbett

137 posts in 3420 days


#15 posted 12-20-2016 01:51 AM

This may have already been answered, but how many circuits is your current 200 amp panel rated for and how many circuits are you currently using? If you are four circuits shy of the maximum, you may be able to gain the spaces you need my switching some of your existing single pole breakers to tandem breakers. For example, if you have ten single pole breakers and changed them to five tandem breakers, you would gain four spaces for your two 240v circuits and one space for a tandem 120v breaker for your two 120v lines. The maximum number of circuits should be located somewhere on the inside of the panel.

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