Color Coding Ungrounded Conductors

Does the NEC (or other code reference) specifically address color coding of ungrounded conductors in residential panels with respect to white (unlabled) being used as such?

If so, I could sure use a quote!


See 2003 IRC E3307.3 …please…don’t make me type it all in by hand :slight_smile:

White is a grounded conductor, and does in fact need identification.
Ungrounded conductors can both be black, no extra identification is needed.

Some areas will allow the stripe on the neutral of URD cable as identification, although it does not meet the letter of the NEC.


***200.6 Means of Identifying Grounded Conductors

(B) Sizes Larger Than 6 AWG** An insulated grounded conductor larger than 6 AWG shall be identified by one of the following means:

(1) By a continuous white or gray outer finish.
(2) By three continuous white stripes along its entire length on other than green insulation.
(3) At the time of installation, by a distinctive white or gray marking at its terminations. This marking shall encircle the conductor or insulation.*

Thanks Mike!

I found it quoted elsewhere! :slight_smile:

Thanks Speedy!:slight_smile:

Good deal…did it say:


Except for the very last sentence. But I think they will get the gist of it. I called it out on an inspection in June and just now the electrician was looking at it and thought I was calling out the grounded conductor on an AFCI:roll:. I guess the picture with a red circle and arrow didn’t help…

It was the breaker just above one of the AFCI’s…:slight_smile:

Client was looking for a code source to give to the builder’s electrician.

All is well (I hope):smiley:

It might be noted that the requirement to reidentify a white wire in a switch loop is fairly recent (1999 or 2002?) so in older homes you might see a white and black on a switch. The white should be the hot leg and the black the switched leg so you end up with a hot (switched) black and a white neutral where it attaches to the luminaire. That makes it line up with the pigtail on the light. If you see a black and a white under a wirenut in the box, that should tip you off that this is the outgoing switch loop leg … if you are an old guy who worked before 2002.

200.7 Exception 1 of the 1968 code cycle had the requirement to change the color of a white conductor when it was being used for an ungrounded conductor.

In 1996 it says
200-7 ex2 <cable switch loop verbiage> … “In these applications re-identification of the white or natural gray conductor shall not be required”.

That goes away in 1999.

I just looked and ex2 goes as far back as 75, the oldest book I have handy. What does it say in 68 again?

Let’s start with the original question:

Then you made your statement about switch loops and I came back to the original question to show that in the panel the requirement has been in the code for several years.

As one can see from the 1968 code cycle in the **panel **the conductor is required to be identified as something other than white or gray when being used as an ungrounded conductor.

As you have pointed out the requirement about switch loops is correct but is not part of the original post.
I was just trying to keep the original poster from confusing the switch loop from the conductors found in a panel.

I agree Mike, that is why I was very clear to differentiate “switch loops” when I made the original comment.

Good deal this means we are all on the same page, and thank you.