Residential Wiring Colors....GREEN?

[Josh]

My 1950s vintage house has the armored flexible conduit. Most of the circuits have the standard black/hot white/neutral color scheme. For some reason, the 20A circuit I want to modify uses a GREEN 12-gauge wire all the way from the breaker to the hot outlet terminal in my garage wall. I plan on changing that outlet to a double outlet to eliminate the need for extention cords and/or adapters, and also add another single outlet 10 feet away. That same circuit feeds some outlets in my living room, I assume via a junction box somewhere in the attic. Thankfully, they did use white for the neutral! Here's what I'm wondering:

Should I continue with the green/hot color scheme for that circuit by putting a wire nut and green pigtails on the green wire inside the new double outlet box, and run a longer green wire from the wire nut to the new single outlet, or simply change to the standard black/hot wiring exiting the wire nut? The latter option would have the green/ hot wire coming into the wire nut in the new double outlet box, two black pigtails feeding the hot sides of the two new outlets, and a longer black wire coming out of the wire nut to feed the new single outlet further along the wall. The neutral, in either case, would be the standard white.

I can see the advantage of having the entire circuit the same color (green), but it looks a little odd to have a green wire feeding the hot side of the outlet(s) AND another short green wire grounding the outlet to the sheet metal screw in the back of the outlet box.

No one except ME will probably ever see inside the outlet box, but since it's semi-permanent I'd like to do it right.

[Doug Miller]

That's a Code violation. If feasible, you should remove that green wire, and replace it with black or red. If removing it is not feasible, permanently mark it at both ends either black or red.

NO!!!

Green insulation is permitted for one thing, and one thing only, under the National Electrical Code: the equipment grounding conductor. Using green wires for hot conductors is potentially lethal: someone else, later, may assume that's a ground wire and therefore not live.

Yes.

There are *no* advantages to having the circuit incorrectly color-coded.

So mark the green hot wire either black or red -- or replace it.

Then do it right: use the proper color-coding.

Ground: green, green with a yellow stripe, or bare Neutral: white or gray Hot: any other color, usually black, sometimes red, occasionally blue, yellow, or orange.

[RBM]

I'm assuming that this is rubber covered cloth wire, and not plastic, and this is flexible steel conduit, and not BX cable. There should never be a green conductor carrying current, other than fault current of an equipment ground. There really isn't a legal way to correct it other than pulling it out and replacing it with any color but white, grey, or green. If it is in fact, flexible conduit, you should be able to tie a new conductor onto the green one and pull it through the conduit.

[dpb]

Josh wrote: ..

While I'll agree it's not Code-compliant as others have said, on existing work I'd not bother to change out a wire; just mark the ends and go on w/ correct color coding from there.

This is, of course, assuming that they did actually do what is said and not a mis-identification...

[Shaun Eli]

To head off potential danger in the future you might want to put a sticker on the breaker box that says something like "Caution-- there are green wires in the walls that are NOT ground but the HOT wire." You probably don't want to come home one day to find a dead electrician in the house.

copyright 2010 Shaun Eli

[Josh]

Pulling the entire green wire through and replacing it with blk or red isn't feasible. The green and white enter the outlet box and don't leave. But since there are other outlets in the living room on this circuit, there has to be a junction box somewhere in the house that the green wire goes into and branches out of. It's probably in the attic, and since I have a relatively flat roof, hardly any crawl space up there and lots of loose fill insulation, I ain't going up there!

I'm going to leave that green wire alone, maybe mark the ends and put the warning sticker on the breaker box which one of you recommended, and use black 12 gauge from the wire nut onwards.

I guess the original electrician was color blind. But the wire has done its job for 51 years and counting without, as Shaun stated, killing any electricians.

[dpb]

Marking it is good; I'd guess the run was done because was out of black/red at the time and didn't take the time/trouble to go get additional wire for one run. It would seem more likely was a DIY'er rather than licensed electrician but in existing work it doesn't make a whole lot of sense to pull it only for the insulation color.

If ends are marked and it is used as hot it will be patently clear to any electrician long before there's an issue. It's not quite like the situation of white (neutral) in switch leg where there isn't another black conductor to be used but again since it's existing, "close enuff".

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[RBM]

[terry]

Anyone else can take me apart for this ............... but if it was in my house and in good condition and the breaker is the appropriate size for the gauge of 'smallest' wire on that whole circuit (see below) then I'd generously mark both ends of that green hot wire either with red nail polish or black paint or sleeve it with some black tubing (also mark 'green wire' on the circuit breaker record) and carry on from there. But is that circuit correctly grounded, is it????? BTW recently a neighbour working on his basement asked me me to hook up two outlets from an existing circuit. He had used 14AWG for the extension which he had bought because it was cheaper than 12AWG! So I warned him before we started that THAT circuit MUST be breaker-ed back at the panel at 15 amps. A short while ago he had an electrician replace his old fuse panel with a breaker-ed panel. Fuse were an odd choice, because our house built about same time has a generous supply of breakers and two pony panels! Fortunately it was a 15 amp breaker- ed circuit and with very little, if anything else, on it! So his outlets will be OK.

[hrhofmann]

NO one seems to have mentioned GFCIs for the garage outlets.

[RBM]

Anyone else can take me apart for this ............... but if it was in my house and in good condition and the breaker is the appropriate size for the gauge of 'smallest' wire on that whole circuit (see below) then I'd generously mark both ends of that green hot wire either with red nail polish or black paint or sleeve it with some black tubing (also mark 'green wire' on the circuit breaker record) and carry on from there. But is that circuit correctly grounded, is it????? BTW recently a neighbour working on his basement asked me me to hook up two outlets from an existing circuit. He had used 14AWG for the extension which he had bought because it was cheaper than 12AWG! So I warned him before we started that THAT circuit MUST be breaker-ed back at the panel at 15 amps. A short while ago he had an electrician replace his old fuse panel with a breaker-ed panel. Fuse were an odd choice, because our house built about same time has a generous supply of breakers and two pony panels! Fortunately it was a 15 amp breaker- ed circuit and with very little, if anything else, on it! So his outlets will be OK.

Good point about the grounding. The OP hasn't clearly specified what the conductors are in, but it does sound like some form of Greenfield, which is only acceptable as an EGC for circuits 20 amps or less, and lengths not exceeding 6 feet.

[Josh]

When I bought the 50s vintage house in 1971, all the outlets were the old 2-prong type. The only ground was outlet ears and/or outlet mounting screws into the metal outlet boxes and back to the breaker box via the flexible armored steel conduit. Over the years I've replaced all the outlets with 3-prong type, drilled a hole in the back of the outlet box for a sheet metal screw, and connected a 6 inch green 12 gauge wire from the screw to the outlet ground connector. That's the case with the garage outlet I'm modifying from single to double.

If I use an AC voltmeter or a small neon circuit tester to measure from outlet hot to neutral, it naturally reads approximately 117 v. If I measure between the outlet hot to the metal outlet box, or the ground connector on the outlet, it reads the same 117v so I know the ground path is in tact all the way back to the breaker box. Fortunately, none of the previous owners replaced any of the metal outlet boxes with the blue plastic ones! I've never figured out why anyone would want the plastic boxes but I guess that would be a completely new topic/thread.

[RBM]

Plastic boxes can be bought in large 22 cu. inch size for about 1/4 of the price of a standard 2x3 steel box. More room, for the buck, less chance of cutting a conductor and having it ground out, but you cannot feed a plastic box with a metal conduit, which may be the reason previous owners didn't

[dpb]

RBM wrote: ...

Certainly, but...it's already there and been there for some years.

I'm not anal-enough to rip it out just because some previous doofus ran a green wire when shoulda' pulled a black/red/anything_but_white_or_green one...

Again, this is based on the previous qualification OP has correctly identified the situation and the conductor is continuous on the neutral from the breaker to the other end and is _NOT_ also a ground doubling as a neutral but is merely a misuse of green-insulated wire as a neutral.

If one of the other faults is also present then it definitely ought to be corrected.

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[RBM]

I agree, it's been there for a l "No one except ME will probably ever see inside the outlet box, but since it's semi-permanent I'd like to do it right."

[Bob]

I've seen similar wiring schemes in 50's wiring in Los Angeles, which required conduit wiring at the time. Evidently at one time green was not reserved for use as a grounding conductor. You may be able go grandfather in what is in place now, but if you're extending the circuit use another color.

Also keep in mind that flexible conduit is not suitable as a grounding conductor, although it may have served such a purpose at one time. If feasible you may want to consider running a new hot wire from the breaker to the first outlet, leaving the green wire available for grounding.

[RBM]

You may be able go

I believe that existing , previously approved wiring is inherently grandfathered provided it hasn't been altered . If his entire house was wired using green conductors for the hot legs, it might give credence to your theory, but as it was just this one circuit,it's more likely that it was just sloppy work. The original wiring didn't use an equipment ground and didn't have grounded outlets. To be Nec compliant, the Op should not have replaced the non grounding outlets with grounding outlets, unless he pulled an equipment grounding conductor through the greenfield.

[dpb]

RBM wrote: ...

Well, we can't tell; I added the caveat first go that presuming OP did indeed verify this is a continuous connection back to the neutral bus, not the ground. If that really is the case, it isn't unsafe electrically, just not Code-compliant on the colors.

It could quite easily be a two-wire circuit in the time frame which are grandfathered.

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[terry]

Just a reminder to make it clear that we are discussing a Green 'HOT' wire, not a Green neutral; the OP in part wrote this as follows in his original post.

Quote: "For some reason, the 20A circuit I want to modify uses a GREEN 12- gauge wire all the way from the breaker to the hot outlet terminal in my garage wall. ......... "

Mention it' because in one post somebody seems to assume green =3D neutral! But that's not what the OP posted.

[terry]

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Good point; cos we have a situation with a few 120 volt and 240 volt outlets on the same circuit above a garage work bench (concrete floor) and near the garage door.

I guess the proper answer is get a double pole GFI equipped breaker (Square D type) for the whole circuit?

The reason for the 240 volt outlets is that we have a few tools of that voltage (both UK vintage and surprisingly a 1950s 'Miller Falls' US electric hand drill!) and couple of cordless battery chargers brought from working in the Middle East, that are also 240 volt. And darn it, I forgot to 'Edison' wire the regular 120 volt outlets at the time. Not that it matters there will not be heavy load on them anyway. Also we have a heavy 240v welder outlet on an individual breaker in an adjacent room anyway.

Comment welcomed.