suggestions for fixing a wiring mess in the shop...

Long story short, I have a 30-amp, double-pole breaker wired to 10/2 cable. Black and white to the two poles on the breaker, bare ground to the combined neutral/ground bus bar.
The shop has four 20A receptacles. Black to the "hot" side, white to the "neutral" side, and bare to the green ground screw. I was wiring them like I've wired every other receptacle in my life (all 110)... What I didn't realize was that I had a double pole breaker. Rather, I asked for a 30A breaker (since I had pulled 10-ga. wire), and never considered the ramifications of the fact that the thing he handed me was double-pole; not even as I merrily hooked it up like all the other double-pole breakers in the panel.
I just didn't think. I've done some wiring projects successfully, and I fell into the trap of thinking I knew what I was doing. I obviously didn't, and I'm very lucky that the worst consequence of this mishap was a blown ballast and a fried voltometer.
What I have is half-assed 220. I'm not sure if I could just rewire my big motors and use this with 10/2 cable (or maybe run an extra red wire) or really what my options are at this point.
Seems the easy thing is to just throw away the $60 breaker (can't return it, and I have no other use for it) and buy a 20A SINGLE POLE, then continue with the original plan, but then there's the non-trivial problem that I have cut the neutral too short to make it to the bus bar, and I already took up the slack at both ends of the run.
It's a big mess. I deserve all the "hire an electrician before you burn your house down, you moron" type comments that I'm sure will follow, but I'm *not* stupid. I just had my head up my ass. I could use some advice, on how to get it out without electrocuting myself, or burning anything down.
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Silvan wrote:

Wow. First time I've heard of that one. ;-)

Well, I can see three possible solutions. Which one is best depends on your particular needs and how your shop is laid out I suppose...
(1) As you suggested, buy a 20A single pole breaker and call it a day. It sounds like this is what you were really trying to do to begin with, so this may be the best solution. As for the neutral length problem, you could simply wire-nut another piece of neutral conductor on to the existing one. I don't know if a wire-nut inside of a breaker panel is allowable by code where you are, but then again, what you have now certainly is not, so you'll be in much better shape than you are now. :-) Having the larger wire is not a problem or a safety concern - only having wire too small for the breaker would be a problem, not vice-versa.
(2) Same as #1, but re-run 12/2 wire, since this is really all that you need for a 20A circuit. That way there isn't a wire nut, and no one will look at this 30 years from now and wonder why the heck someone used 10/2 wire for a 20A circuit. :-) "Wire is cheap", but depending on how your shop is laid out and how far it is to the panel, re-pulling the wire may not be an attractive solution. (3) As you also suggested, use it as a 240V circuit (after substituting the correct receptacles) for your big motors (and presumably run an additional circuit for 120V use, since I assume you have some things that won't run on 240V.) This solution is the most work, but there are some good reasons for doing this: at 240V, motors (or anything else for that matter) draw half the amps. This means significantly less draw on the circuit, less voltage drop, quicker motor starts, etc. It can also help to better balance your service load. I have my large motors (table saw and band saw) re-wired for 240V in my shop, and would never look back. They just plain work better, especially the table saw.

Well, you may need it some day, so don't chuck it. Or you may be able to sell it on-line to someone who *can* use it. You'll lose something on it because it's "used", but it's better than just throwing it away.
Note that in addition to the three ideas above, you *could* simply move the white wire to the neutral bar (after extending it with a wire nut so it will reach), and leave everything else as is, still using the 30A breaker. You'd just be using only one side of it, which would work fine. The other side of the breaker would be unused, so it would waste a slot in your panel, but it would work fine. This seems rather mickey-moused to me however, and having 20A circuits on a 30A breaker is probably a code violation (on top of having a wire-nut in your panel), so I wouldn't really recommend it. It would work though.
Hope this helps.
Disclaimer: I'm not an electrician, I'm a woodworker.
- Jeff
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Wilson Lamb wrote:

Well, he has a double-pole breaker and should probably replace it with a single-pole if he does use it as a 120V circuit, for the reasons I mentioned before (wasting a slot in the panel, meeting code, etc.) I just figured that if he had to replace the breaker anyway, he might as well go with a 20A. It'll be cheaper, and I didn't know if you can legally put a 30A breaker on a circuit with 20A receptacles. Perhaps you can, I just don't know, so I erred on the side of caution. Obviously a 30A breaker will protect the wire, which is it's main job, but I just didn't know if it was up to code to use it with standard 15A or 20A receptacles. I've never seen a circuit wired that way before.

It sure will. Been there, done that. :-) That's yet another reason I decided to go 240V in my shop for everything that I could (thus far that's only two of my machines, but growing!)

The problem though is that he ran three wire cable (2 + ground), so he can either use it as 120 (hot and neutral) or 240 (hot and hot), but to run a subpanel off of it he'd need four wire cable, so he could have both the two hots and neutral. So, to run a sub-panel, he'd need to pull new wire, and he's back where he started again. :-)
FWIW, I put an 8-position sub-panel in my shop, feeding it with 6/3+g, and a 50A breaker. Right now I have a 20A 120V circuit for benchtop and hand- held tools, and a 20A 240V circuit for my table saw and band saw (I work alone and would therefore never have both running at once, so I kept them on the same circuit.) When I finally get a dust collector I'll have room to add a dedicated circuit for it, and will still have 3 positions left in the panel for future expansion if I need it, enough for a 240V and a 120V circuit, or three 120V circuits. It's been working out pretty well for me so far.
- Jeff
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Jeff Morris wrote:

I may have just stupidly been copying the rest of my house. 15A receptacles on 20A circuits. Only 14-ga. wire. I'll bet that isn't to code either. The more I look at my wiring, the more I realize there's probably a reason why the underside of my tubs and other hidden, unfinished spaces are filled with Budweiser cans.
Not that I've done any better for myself, mind you!

I don't know if I could make it reach far enough to feed a sub panel anyway without pulling new wire. Maybe I could use the existing wire to pull the new one, since I doubt I will ever manage to wrangle a fish tape through that thing again.
Thanks to both for all the tips. I think what I'll do is pull the breaker, buy a 20A single pole, and then consider a sub panel in the future, some day after I have done a lot of homework. I only have one machine with clear instructions for how to rewire as 220 anyway, and it's my horizontal (metal-cutting) bandsaw, which I don't really consider the prime candidate for 220ization. It may be possible to do others as well, but that's a topic for more homework.
In the meantime, I've been running the shop with a horrible rat's nest of extension chords for years, and I expect that a 20A dedicated circuit fed with oversized wire will probably really improve things in of itself. That's all I was *trying* to do in the first place. (So why did I buy a 30A breaker? I don't know. Tim Taylor syndrome?)
The neutral problem I can just take care of with a junction box, if I can't make it stretch; if it's OK to put a junction box in the attic. I *think* it *is* OK to put one in the attic, but not inside finished wall space.
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Silvan writes:

You'd win that bet. #12 wire on 20 amp circuits. We had some of those before the basement fire. It is being corrected. I hope. And I will check.

You can run the wire through a junciton box, running longer pieces from there to your subpanel.
Sounds like to me, though, that you're better off pulling new cable of the correct size and type.

Yup. Never inside finished wall space.
Charlie Self
"I know how hard it is for you to put food on your family." George W. Bush, Greater Nashua,N.H., Chamber of Commerce, Jan. 27, 2000
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*INDEED*

In theory, yes. It is _almost_certain_ to be a violation of electrical code to have a 'white' wire that is 'hot'. which *is*, as your found out, what you have.

Is the wiring 'in conduit', or is it something like 'romex'? If in conduit, then pulling an extra conductor _is_ a viable option. If not in conduit, and there is any sort of governing electrical code, its a 'sure bet' that it is -not- allowed. And, even if it is, you *don't* want to do that. The risk of it getting 'nicked', cut, etc. is just too great.

If it comes to that, *don't* throw that breaker away. You might have use for it someday in the future, OR, after identifying what kind of a panel it fits (from the price, I'm guessing "Federal Pacific"), you might be able to sell it to somebody here on the wreck (for maybe 2/3 of your cost).

You're right. You've got a problem.
STEP ONE. *DISCONNECT*EVERYTHING* from that 30-A 2-pole breaker, and tape off the loose ends. This eliminates the possibility of additional accidents while you 'consider' how to fix the problem.
What your options are depends on where you live, and what electrical code there allows.
In places with 'modern' electrical code, you are *NOT* allowed to have any splices, or other interconnects _inside_ the breaker panel. Has to be in a separate junction box. *DUMB*, *STUPID*, but true -- and I've got the 3-months-ago rewired main panel and junction box to prove it. All but _two_ circuits go from the panel through the junction box ( yeah, *big* junction box :).
To get the 'white' NEUTRAL to reach the neutral bus, you have a couple of options: 1) replace the run with wire of 'adequate' length. 2) install a junction box _outside_ the panel, and splice on an additional length of wire at that point.
*NOTE* you've just rediscovered why it is a GOOD IDEA(tm) to _leave_ as much slack as you reasonably can, at _both_ ends of the run.
As far as the breaker, I don't know anything that prohibits using "only one side" of a double-pole breaker for a single circuit. It is, obviously, "inefficent" use of panel space to do so, But I don't think that that is a 'crime' under electrical code. Check with a professional in your area to confirm.
You _do_ need to check electrical code restrictions in your locale, re: the use of 30A breakers. A fair number of jurisdictions restrict circuits above 20A to a _single_ outlet. 20A is considered an 'appliance' circuit; any thing above that is classed as 'equipment'/'machinery'. Different animals, according to the NEC.
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Robert Bonomi wrote:

I thought that it was permissable if the white wire was marked at both ends as a hot (using either black tape or permanent marker for instance)? I've seen several such installations pass inspection, and fairly recently at that, so I thought it was permissable. Perhaps they just aren't strict about that around here though.
- Jeff
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It is certainly permissible for a properly installed 220 circuit ... even _required_ in most locales ... if not just plain common sense.
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Roy Smith wrote:

Turns out I did leave enough slack, after I shuffled things in the attic, so this is pretty much a no-brainer now. Get the right breaker, and continue from here. With 10/2 wire and a 20A breaker and 20A receptacles, I should be fine.
An expensive lesson, but not as expensive as it might have been. $100+ down the toilet, but nobody dead, and nothing charred except some cheap light fixtures.
I did try the remaining lights briefly (on an extension chord), and another one of them let the smoke out immediately, so I pulled every light, cut the chords off and wrote "FRIED" on them with a sharpie to prevent some curbside deal seeker from having an accident.

Yeah, obviously, WTF was I thinking???

Good, sound advice that I can't argue with. I sure haven't done a very good job of demonstrating competence on this job. Or on a lot of other things lately.
I should stick to building catapults.

I'll hang onto the thing for awhile, I suppose, in case I run into someone who does need it. Ask me about it again in six months to a year, and if it's still in a drawer somewhere, you can have it.
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I assume these are florescent light fixtures? Any that you did not turn on with the 220, even if you wired them up, should still be OK. If you turned them on, they are fried. But the ones you didn't try to use will be fine.
Bill Ranck Blacksburg, Va.
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