210-5. Color Code. Where installed in raceways, as aluminum sheathed cable, as open work, or as concealed knob-and-tube work, the conductors of multiwire branch circuits connected to the same system shall conform to the following color code. Three-wire circuits - one black, one white, one red; four-wire circuits - one black, one white, one red, one blue; five-wire circuits - one black, one white, one red, one blue, one yellow. Where more than one multiwire branch circuit is carried through a single raceway the ungrounded conductors of the additional circuit may be of colors other than those specified. All circuit conductors of the same color shall be connected to the same ungrounded feeder conductor throughout the installation.
This passage of 210-5 is unchanged from previous editions of the Code. Text was added in '68 after the quote above to cover the color of the grounding conductor, where used.
'71 NEC 210-5. Color Code for Branch Circuits. The section is broken into parts (a) Grounded Conductor, (b) Grounding Conductor & (c) Ungrounded Conductor. Section 210-5(c) Ungrounded Conductor itself no longer specifies colors, except to exculde the colors used in (a) & (b), and is followed with a fine print note:
It is recommended for a basic single wiring system that the following colors be used: 3-wire circuits, 1 black, 1 white and 1 red; 4-wire circuts, 1 black, 1 white, 1 red, and 1 blue.
'75 NEC 210-5(c) the FPN is deleted and the wording is simplified to:
210-5 Color Code for Branch Circuits (c) Ungrounded Conductor. Ungrounded conductors of different voltages shall be of different color or indentified by other means.
What was the CMP reasoning for the removal of the color code?
[This message has been edited by ElectricAL (edited 01-22-2003).]
Is it safer to have color codes or not to have them? You can argue that no color codes is safer because then you have to test and verify everything before working on it. With color codes, we all get in the habit of relying on them. What happens when we work on an installation that is not code compliant? Has anyone ever cut a green wire and found it to be hot??? I have. Yes, I should have checked, but I relied on the color code. Don
Re: Why Did The Color Code Get Deleted?#83232 01/22/0307:52 PM01/22/0307:52 PM
Found a green on a breaker the other day in a 208Y 200 amp sub-panel. Who knows when it was done? For kickers, this sub-panel's neutral was bonded. I'm never surprised anymore. In fact, I expect it. Years of working in cable wired facilities gets you used to all black wiring. I never trust colors until I test them. I too have some homemade wire strippers, I too have seen the "light".
Re: Why Did The Color Code Get Deleted?#83234 01/23/0307:47 PM01/23/0307:47 PM
Even the NFPA (author of the NEC) can't settle on a color code; note that their "standard for industrial machinery" has an entirely different scheme. BOY-o-boy! Then there are the practices of coding to identify switch legs, different voltages, UPS/IG circuits, and so on. Sometimes "good practices" are not "good laws."
Re: Why Did The Color Code Get Deleted?#83235 01/25/0307:16 AM01/25/0307:16 AM
200.7 FPN: The color gray may have been used in the past as an ungrounded conductor. Care should be taken when working on existing systems.
I understand that previous NEC editions specified white or "natural gray" for a grounded conductor.
When exactly did the NEC first specify gray (natural or otherwise) as a grounded conductor? It seems to me that there's plenty of room for errors when a color code is suddenly changed (the U.K. in 1970 being a good example).
Re: Why Did The Color Code Get Deleted?#83236 02/01/0309:34 PM02/01/0309:34 PM
Thanks to Joe T. for sending scans of the following:
July, 1970, "Preprint" of the Proposed Amendments for the 1971 NEC
PROPOSAL NO. 16:
Amend Section 210-5 to read:
210-5: Color Code for Branch Circuits. (a) Grounded Conductor. The grounded conductor of a branch circuit shall be identified by a continuous white or natural gray color. Exception. The grounded conductors of Type MI cable shall be identified by distinctive marking at the terminals during the process of installation.
(b) Grounding Conductor. The grounding conductor of a branch circuit shall be identified by a continuous green color or a continuous green color with one or more yellow stripes as insulation for internal wiring of equipment, except where such wiring serves as the lead wires to which the branch circuit conductors attach.
(c) Ungrounded Conductors. The ungrounded conductors of a branch circuit shall be identified by any color other than as specified in (a) and (b) above. All ungrounded conductors of the same color shall be connected to the same ungrounded feeder conductor. FINE PRINT NOTE: See Section 200-7 for use of grounded conductors under certain conditions.
(1) This prohibits the colors reserved for grounded and grounding conductors to be used for ungrounded conductors, but permits the ungrounded conductors to be any color so long as all conductors of the same color are connected to the same phase. There is no reason for restricting the color on ungrounded conductors. (2) This eliminates discrimination by requiring color coding for all wiring methods instead of for some methods only. If it is necessary for safety for some systems, it should be necessary for all systems. (3) The provision for more than one color for the same phase where run through the same raceway has been deleted as unnecessary. (4) This spells out the requirements for grounding conductors under a proper heading in liwu of the arrangement in the 1968 Code.
Accept Proposal No. 16 with paragraph (c) revised as follows:
(c) Ungrounded Conductor. Where installed in raceways as open work or as concealed knob-and-tube work, the ungrounded conductor shall be identified by any color other than as specified in (a) and (b) above. All ungrounded conductors of the same color shall be connected to the same ungrounded feeder conductor and the conductors for systems of different voltages shall be of different colors. Exception: As permitted in Section 200-7. FINE PRINT NOTE: It is recommended for a basic single wiring system that the following colors be used: 3-wire circuits, 1 black, 1 white and 1 red; 4-wire circuits, 1 black, 1 white, 1 red, and 1 blue.