Can you use white for one leg of 240V circuit?

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I agree, labor costs would be through the roof. If you were building your own maybe. The materials would still be more but not as ridiculously higher as the labor would be. The benefit is not enough to make me consider it. It's not that hard to pull more wire in old residential work. You just have to go the long way occasionally.
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On Fri, 6 May 2011 05:33:32 -0700 (PDT), jamesgangnc

Chicago still requires EMT in residential the last time I heard but I think you can use Romex out in the burbs.
ENT (smurf) is a good compromise. You get the flexibility of being able to run different wire and not a huge labor factor.
In the addition I did in my house everything going down the block and concrete walls is in smurf. This is poured tie beam construction so what is in the wall is all you will ever get.
http://gfretwell.com/electrical/addition/smurf%20job.jpg
A home run of 3/4" smurf makes it easy to change your mind. There are also low voltage outlets for TV/phone/data.
It all originates in a J box where the home runs start. Changing what does what may be as easy as moving a wire between wire nuts.
http://gfretwell.com/electrical/addition/j_box.jpg
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On Wed, 4 May 2011 04:30:52 -0700 (PDT), jamesgangnc

Running the power to the switch makes a less flexible condition. Places like bedrooms (although they are coming less and less with an overhead light) and living areas where you might want to add a ceiling fan would not have constant power at the light box.
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On 5/3/2011 9:59 AM, jamesgangnc wrote:

It was never acceptable under the NEC.
Whoever sets the electrical rules where you are may have modified NEC, or inspectors may have used their discretion to allow it.

Depends on what "changes" you are talking about. Existing wiring with SE cable (or an insulated ground wire) is explicitly grandfathered in the NEC.
--
bud--

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My home was built in 1990 and water heater is wired with 10-2 with ground. All the elements are 240 and there would be no place to connect a neutral. My electric range was wired for 10-3 with ground....... part of the reason is that at least part of the stove is 120VAC. Diagram of the stove shows an electronics board that gets its power from 110VAC.
Jimmie
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Yes, as long as it's labelled or colored at each end what its color should be. I think It's in the NEC but I can't cite it.
IIRC, and you might want to check this out for sure:
In such a ckt, the norm is: RED = Always hot Blk = switched hot WH = Neutral
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On Sat, 7 May 2011 14:46:49 -0400, "Twayne"

I had a foreman once that ordered purple to use for travelers and switch legs. I always thought that was a good idea.
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wrote:

** That's fine if you're pulling your own conductors. The Nec has no specific colors for switched legs, other than not using the white wire of a cable, as the return from a switch. All colors are considered "hot" except green, white, and natural gray. and no, I have no idea what the difference is between gray, and natural gray.
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On 5/7/2011 2:29 PM, RBM wrote:

Natural gray is really old and cranky wire. ^_^
TDD
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The Daring Dufas posted for all of us...

Is the "Just for Wire" ?
--
Tekkie

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On 5/9/2011 10:08 AM, Tekkie wrote:

Yea, whenever you want to renew the color of your old wiring. It renews the color of the wiring but doesn't do much for the cracks in the insulation. There are other products that work for filling in the cracks and wrinkles in your old wiring, I think one is called "Almay Electra". ^_^
TDD
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Purple must have been used in 120/240v service for travellers... It would have been confused as a phase conductor in 277/480v Wye power systems...
Where it wouldn't be confused with the phase conductors -- in serious commercial/industrial applications all of the wiring from the panel to the farthest end of each circuit is colored by phase:
In 120/240v systems it is common to use the following colors for circuit conductors:
L1: Black L2: Red L3: Blue N: White G: Green or Green/Yellow stripe
Where you would also mark a "high leg" in a Delta wired system with Orange...
In 277/480v systems you would use the following colors:
L1: Brown L2: Orange (delta) Purple (wye) L3: Yellow N: Grey G: Green
Those color "common practices" are not code but they are generally adhered to due to the ease of servicing such installations without needing to resort to numbering each conductor and using wiring diagrams every time you open up connections to work on them... When you remove a cover plate on a switch for lighting and see the colors of the wires you would know which voltage you are working on...
As far as switch legs in residential construction:
White in a two-wire cable used as a switch leg is always to be the supply side of the leg, the switched load is to be on the Black conductor... Although this is going to be a moot point going forward as there is now a new code requirement that a neutral be provided at every switch location... That means three wire cables and White being the neutral...
In general practice in switch circuits Black is usually constant power, only being switched if there are multiple groups of lighting being fed off the one cable -- this is useful where you might have a ceiling fan where the fan portion is controlled by the pull string on the fan or an integral remote control... The lights on the fan would be powered by the Red conductor which is switched...
This logic also applies to wiring for receptacles, where with a three wire cable you could have a switched receptacle (or several switched receptacles) in a room where the Black conductor is constant power and the Red conductor is the switched load...
If only more people wired their houses with three or four wire cable they would be able to do many more interesting things later on down the road without needing to rip into the walls or snake additional wires in finished walls...
~~ Evan
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On 5/7/2011 7:49 PM, Evan wrote:

The guy insisting on purple for travelers may have been using 277volt lighting. Most of the 120 volt travelers I've ever seen were blue.
TDD
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wrote:

You wouldn't want to use the purple color out of phase...
So perhaps on a lighting circuit fed from L2 he could have used purple travelers...
Some installations are fairly anal about maintaining that color coding so you can tell instantly what phase your circuit is powered on the second you take off a cover plate or open an enclosure...
~~ Evan
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In wrote:

That sounds more like a European spec; brown, blue &
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Nope... Just sounds like you haven't worked in many commercial or industrial facilities is all...
~~ Evan
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On Mon, 2 May 2011 04:45:43 -0700 (PDT), jamesgangnc

Not really. The code called that 3d wire a "neutral" that was also being used as a ground and the neutral was always required to be an insulated conductor. I agree a lot of inspectors ignored this violation but that did not make it right.
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On May 2, 10:11am, snipped-for-privacy@aol.com wrote:

Millions of existing installations suggest that at some point the code did not make that distinction. Or it was hugely ignored. Either way there are a LOT of 10/2 dryer circuits.
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Since the 120 V circuit was usually a timer, you did not have much of a safety issue. If the dryer motor was a 120 V motor, things were a little less safe. The new rules cover all situations.
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