Shop Wiring Suggestions

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I am in the process of applying for an electrical permit from the township. I have an existing 200 amp service which has two breaker spots available. From here I am going to run a 100 amp subpanel to support new outlets in the shop. The current drawing I am working on can be see here:
http://www.hms3.com/images/basement.jpg
I plan on running at least 1 240v outlet for a table saw. Then I was going to run a couple more outlets to support various other shop tools.
Some questions I have:
1. I am wondering if I should run 30 amp breakers with 10 gauge wire for everything or wether 20 amp breakers with 12 guage would suffice.
2. The table saw that I am planning for the shop rates at 240v 13 amp. Will that pull more than 13 amp when it is first turned on? It seems like there is always a spike when a motor first turns on.
3. At this point I don't have plans for another tool that requires 240, and I don't have a whole lot of space in the shop. I don't think I should bother running another 240, but does it make sense to run a second one just in case?
4. The shop part of the basement is unfinished and has exposed studs which are the back of the finished part of the basement. Right now all existing recepticals are just connected to these studs with NM electrical cable running through the studs back to the existing panel. Is it OK to duplicate this practice with the new subpanel? (I wired an unfinished basement without studs some years ago and used aluminum conduit. I fealt really good about it. It doesn't sit well having all this cable exposed.)
5. In the existing wiring there is a bunch of NM cable that runs over some ceiling beams. It isn't secured and kind of weaves in and out of each other. Is that up to code? It seems odd.
6. What kind of wire is recommended to run between the panels? It needs to be rated to 100 amp and have 3 wires and a ground. I believe I read that the grounding is done differently on the subpanel vs the main panel because one wants the shortest path to ground. Could someone elaborate?
7. The existing panel is Square D, but I have heard some complaints and was considering using GE for the new one. Should I use Square D for the new panel to remain consistent?
Thanks, Howard
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Howard Swope wrote:

Sorry I've been lurking but here is my $0.02 I would run all the duplex outlets with 12 guage wire with a 20 amp breaker protecting 2 or 3.

I would think a 20 amp breaker would work but I'm not positive on this. You might even have to have a 30 amp breaker, but I would run aleast 10 guage wire to it.

If it was me I would run the extra outlet.

You can run NM cable inside walls like your describing. If you don't have a joisted wall to contain the wire you need to use conduit, but then you have to use thhn or thwn wire. You also have to staple the wire within 8 inches of the box and every 4ft there after.

It can be run like that, but I can't remember if the NEC requires it to be stapled or not. I always secure it down with a staple every other joist.

3/3 is rated for a 100 amp sub, but if you can afford it run 2/3.

I would stick to SquareD so that you don't have to buy 2 different kinds of breakers. But I've not heard of any complaints about SquareD. Here in Tennessee SquareD is one of the popular brands of electrical products.

My answers are all based on the info that I attained over the years and my recent sub panel install that I had to do for my remodel. A good book if for nothing else but for the NEC code information is "Black & Decker The Complete Guide to Home Wiring" it is sold at Lowes. I picked it up so I could see what new code changes I had to be aware of. But if your unfamiliar of how to do something, this book will explain it step by step. I don't do electrical for a living so I sometimes need a little nudge. Of course I learned all the woodworking, electrical and plumbing from the best, my father.
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All the Best
Dale Miller
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Howard Swope wrote: > I am in the process of applying for an electrical permit from the > township. > I have an existing 200 amp service which has two breaker spots available. > From here I am going to run a 100 amp subpanel to support new outlets in > the > shop. The current drawing I am working on can be see here: <snip>
Some suggestions:
SRWIW, unless you are adding A/C or a heat pump to the sub panel, a 2P-60A should be adequate for shop needs.
1) Check existing panel and see if it will accept a 2P-100A sub feed c'bkr. If not, will it accept 2P-60A?
2) Locate new 100A panel in shop area fed by subfeed c'bkr above.
3) Use 1P-20A for outlets.
4) Use 2P-30A for 240V loads
BTW, a 5HP, cap start, cap run air compressor motor requires a 2P-40A c'bkr.
Remember, c'bkrs in a panel must be derated 20% per code.
IOW, a 20A c'bkr can carry 16A on a continuous basis. At higher loads, you are operating on the time portion of the curve.
Have fun.
Lew
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??????
The 20% rule applies only to continuous load, which is defined as a load drawing maximum current for three hours or more. There is absolutely nothing wrong with operating a 20A circuit at 19 or 20 amps for short times.
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Doug Miller (alphageek at milmac dot com)
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12 inches [2005 NEC, Article 334.30]

4.5 feet [Art. 334.30]

No it cannot. Not if he means it's crossing joists, anyway. [Article 334.15(C)]

It does. No farther apart than every 4.5 feet. [Article 334.30]
But not to the bottoms of the joists. [Article 334.15(C)]

That's a Code violation.
Please familiarize yourself with the NEC before attempting to answer any further electrical questions.
Here's a start:
"Where cable is run at angles with joists in unfinished basements, it shall be permissible to secure cables not smaller than two 6 AWG or three 8 AWG conductors directly to the lower edges of the joists. Smaller cables shall be run either through bored holes in joists or on running boards." [Article 334.15(C)]

Just to clarify: 3/3 WG (with ground).
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Doug Miller (alphageek at milmac dot com)
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Doug Miller wrote:

The code book I have say 8 inches.

And it also says 48 inches. I looked up both

Thanks but I read that as the bottom of the joist not the top. Here in my jurisdication all of the electrical contractors run there wire in the attic spaces above the ceiling joists and don't use any holes to run them. And no where do I read in the code that is wrong to do that. And if you had ceiling joist 24 inches OC and stapled the wire down every other joist that is within the 48 inch code.
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Dale Miller
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What code book are you using? Obviously not the National Electrical Code.

What code book are you using? Obviously not the National Electrical Code.
[snip]

Yes.... that was kinda the point....

Nobody was talking about "attic spaces". The original poster wanted advice on wiring for his shop in the *basement*.

You haven't read the right parts of the Code, then. While it doesn't prohibit running cables across the top of joists in an attic, it *does* prohibit doing so without installing guard strips to protect them:
"The installation of [NM] cable in accessible attics or roof spaces shall also comply with 320.23." [2005 NEC, Article 334.23]
"Where run across the top of floor joists, or within 7 feet of floor or floor joists across the face of rafters or studding, in attics and roof spaces that are accessible, the cable shall be protected by substantial guard strips that are at least as high as the cable." [ibid., Art. 320.23(A)]
Of course, as noted above, this is irrelevant to this thread anyway, since the subject of discussion is wiring in an unfinished basement. (You didn't really think the OP had his shop in the attic, did you?)

54 inches.
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Doug Miller (alphageek at milmac dot com)
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Doug Miller wrote:

2005 NEC...for non-metallic boxes you have to staple the NM within 8 inches of the box.

For non-metallic boxes the every 48 inches. All from NEC 314.17 (C) Nonmetallic Boxes and Conduit Bodies.

This maybe irrevalent but as per NEC 334.23 (320.23) "Where this space is not accessible by permanent stairs or ladders, protection shall only be required within 1.8m (6ft) of the nearest edge of scuttle hole or attic entrance.

If you do the searching yourself you will find the code that says 48 inches. I know it's in there I just read it.
All in all your taking the NEC out of context when you only show part of it. The laymen can't understand it this way.
As for the OP if he has solid 2X framed joists, then you would be correct. But if he has truss style joists then he could run the wiring as if it was an attic space, so long as the wire doesn't run under the framing member. But I am pretty sure there is an exception somewhere in the NEC for that too.
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Dale Miller
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No, you don't. The requirement is twelve inches maximum.

The interval between points at which the cable is required to be secured has nothing whatsoever to do with the type of boxes used.

You're misreading that rather badly, I'm afraid.
314.17(C) does *not* require securing the cable at any particular distance from a non-metallic box; rather, it states that *if* the cable is secured within eight inches of a nonmetallic box, then it is not required to secure the cable to the *box*.
And it says nothing whatever about any supposed 48-inch interval.

Right, that's for inaccessible attics. Certainly irrelevant to someone who's wiring a shop in his basement.

I *did* search. It says 4.5 feet. And I cited the section of the Code that specifies 4.5 feet (Article 334.30, in case you've forgotten).

Fine -- then cite the section of the Code where you think you read a requirement to secure NM cable every 48 inches.

To the contrary, it is you who are taking pieces out of context, and you who are failing to understand it -- witness, for example, your misinterpretation of 314.17 as supposedly requiring NM to be secured within 8" of a box. That's not what it says.

No, he could not. If he has truss-style joists, he could run the wiring *through* them, but not *on*top* of them "as if it was an attic space". He's in a basement, remember? What's *on*top* of his joists?

Fine -- cite it.
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Doug Miller (alphageek at milmac dot com)
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I'm not going to fight with you on the NEC issues anymore. Obviously you can't look up the what I stated. The stapling within 8" pertains to non-metallic boxes that have no means of securing them to the box, like metallic boxes having romex connectors. So the exception says that they have to be secured within 8" of the box. I do not have to search the code anymore if you don't believe me and think I'm wrong so be it. But you haven't completely proven that I don't know what I'm talking about.

That was what I was referring to. Not the top of the joist themselves. That would be totally dumb because the subfloor would crush the wire. I'm not that stupid, but it seems you think I am cause you jumped me right off the bat, on my first ever post.

How about you look it up and prove me wrong. Seems you have taking to liking and jumping me, on my first post to the list. Maybe I'm not explaining myself correctly. So I'll tell you what prove me wrong, you obviously think I am.
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Ok what I also don't get is why you are jumping me. Most inspectors don't have a problem if you do better than the code. So if I say 8" and 48" then that is better than code, because you say I'm wrong and code says MAXIMUM 12" and 54" well if that is the case then I'm still doing it correctly anyway. Because last I checked 8" and 48" are less than 12" and 54"
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I'm not "jumping" you, Dale. I'm pointing out the errors in your statements about the requirements of the NEC. It's clear that you have not thoroughly read and understood it, and yet you attempt to answer questions based on your incomplete and incorrect understanding -- and wind up giving incorrect answers as a result. Then you argue with me when I cite (and quote) the provisions of the Code that show what it *really* says.
Incorrect answers to electrical questions can be deadly. If you're going to attempt to answer such questions, you must first know what you're talking about.
So far, you haven't shown persuasive evidence that you do.

Quite true. Securing at 8" from the box, and every 48" thereafter, certainly is Code-compliant. To state that the Code *requires* that, simply is not true.
And it leaves me wondering how many other provisions of the Code you've misunderstood.
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Doug Miller (alphageek at milmac dot com)
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"Dale Miller" wrote in message

LOL ... don't worry too much about it, Dale. Just consider that you've learned early why he's known as the #1 dickhead on the wRec. Save yourself some time and go ahead and plonk his argumentative ass and be done with it ... you'll be glad you did.
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Actually, I think that might be you -- you absolutely can't stand it when anybody disagrees with you, and reply with abuse to any suggestion that you're mistaken. It seems to particularly gall you when you're wrong and I'm right; it's not clear to me exactly why, but I suspect that it might be insecurity over your inability to express yourself clearly.
And you clearly haven't bothered to read this thread before making this insulting and ignorant comment; if you had, you would have seen that Dale's statements about the relevant provisions of the electrical code are factually incorrect, and his defense of them even more so.
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Doug Miller (alphageek at milmac dot com)
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Doug Miller wrote:

My take on the whole matter is that EVERY time the NEC is discussed, there's debate.
Is anyone on this list a licensed master electrician?
If so, let him speak up and resolve this issue, please. If no licensed master electrician, then perhaps a journeyman with experience in the type of wiring contemplated. Otherwise, code citations notwithstanding, this is too serious an area for guesswork of ANY sort. The best possible advice to the OP is to seek assistance locally from someone trained to give it. The second best advice is to buy a book on the topic area and follow it precisely.
Nobody here knows everything about everything. Not even me.
Oh ... and Dale ... now you are learning why this is called 'the wreck'.
Bill
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Swingman wrote:
> Save yourself > some time and go ahead and plonk his argumentative ass and be done with it > ... you'll be glad you did.
Yep.
Lew
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That's pretty funny, really, because I clearly cited the Code provisions that back up my statements -- and *you* are unwilling to look up what *I* provided. It's very clear that I *did* look up what you stated, because I already said once exactly why you're mistaken about what it says.

Actually, most non-metallic boxes *do* have a means of securing the cable to the box.

It does not. It says that *if* the cable is secured within 8" of the box, it is not required to be secured to the box.

You don't. And apparently you'd prefer to be proven wrong than to admit that you made a mistake.
So here's the proof.
The Code article which *you* cited, 314.17(C), says:
"Non-metallic Boxes and Conduit Bodies. [...] In all instances, all permitted wiring methods shall be secured to the boxes. Exception: Where non-metallic sheathed cable or multiconductor type UF cable is used with single gang boxes not larger than a nominal size 57 mm x 100 mm (2 1/4 in x 4 in) mounted in walls or ceilings, and where the cable is fastened within 200 mm (8 in) of the box measured along the sheath and where the sheath extends through a cable knockout not less than 6 mm (1/4 in), securing the cable to the box shall not be required."
This is an exception from the requirement to secure the cable to the *box*, not a requirement to secure the cable to the framing at any particular point.
Nothing there about your mythical 48" requirement, either.

Sorry, my crystal ball is down this week. The only way I have of figuring out what you meant is by reading what you wrote. If you didn't write what you meant, it's hardly reasonable to blame the *reader* for not understanding.

You gave incorrect answers to an electrical question. I corrected your errors. Not my fault if you're unable to handle it.

I've already done that. Haven't you been paying attention to the Code cites I've posted? Go back and look them up.

There isn't any way to correctly explain incorrect statements.

I already did prove you wrong, by citing the relevant articles of the Code. If you think the Code says something different, then you find it and post it.
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Doug Miller (alphageek at milmac dot com)
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If you have an air compressor and leave it on it might be worth a dedicated crcuit for it and any dust control equipment which might run when other equipment is operating

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wrote:

Just "a couple more"? Take my advice: install at least twice as many as you think you need.

I would certainly run at least one 30A 240V circuit, to support (for example) simultaneous use of a dust collector and a table saw, or an air compressor.

Yes, but you don't need to worry about that. The spike is of very short duration. It will do fine on a 20A breaker.

I think so, yes. If you're going to run only one 240V circuit, make it 30A. If you run two, you're fine with both of them 20A.

It meets Code.

If it were my shop, I'd panel the walls with something. Drywall, OSB, plywood, whatever. Protects the wires, gives you convenient places to hang things, reduces by about 99% the number of corners where dust can collect... you can probably think of a dozen other reasons, too, but perhaps the most important (and certainly the most easily overlooked) is that once you have the walls paneled and painted white, your shop will be *much* brighter.

No, that's not up to Code. NM is required to be supported every 4.5 feet. It's also not allowed to be stapled across ceiling joists. When you need to run NM across joists, you must either (a) run the cable through holes bored in the joists, or (b) attach running boards across the joists, and secure the cable to the boards.

For 100A, you need 3-ga copper (minimum). I'm not sure anybody makes NM that large. I'd use individual THHN conductors in rigid non-metallic conduit (PVC electrical conduit -- *not* PVC water pipe).

Yes, it is done differently. Not because you want the shortest path to ground, though, but because you want only *one* path to ground.
Neutral and ground are bonded together in the main panel, and, in fact, the Code does not require (AFAIK) that there even be two separate bars in the main. If there are two bars, they are required to be connected together.
In a subpanel, however, neutral and ground are required to be on two separate bars -- if your subpanel doesn't have a separate grounding bar, you'll have to buy one -- and they *must*not* be connected. Frequently, panels are supplied from the factory with a bonding screw through the neutral bar, that bonds it to the chassis of the panel. If your subpanel has one of those bonding screws, you *must* remove it. The neutral bar in a subpanel *must* be electrically insulated from the panel chassis, and the grounding bar *must* be electrically *continuous* with the chassis.
The four-wire feed coming from the main panel to the subpanel must be connected as follows: - two hot legs, marked red and black, to the lugs on the subpanel main breaker - neutral, marked white or gray, to the neutral bar in the subpanel - ground, marked green or left bare, to the ground bar in the subpanel

It doesn't really matter. What complaints have you heard about Square D?
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Doug Miller (alphageek at milmac dot com)
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