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Scott, I always wonder the same thing. Here is a link: SF Building Code Doesn't LA also have their own building code? Curt
Curt Swartz
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Anybody know when the NEC first suggested orange as the color for a high leg?
I seem to recall from a previous discussion on 4-wire deltas somebody saying that it was common to use red for the high leg back in the 1950s (presumably with black and blue for the A and C phases).
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Paul, I think it was in the 80's possibly late 70's, I will check my pre 90 code books this evening if someone hasn't answered by then.
I can remember the high leg being blue in some installations.
Roger
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Paul, Although I have not found the first reference for "orange." The 1959 NEC confirms e57’s recollection of the short-lived "blue." NEC 1959
210-5. Color Code Where installed in raceways, as open work, or as concealed knob and tube work, the conductors of multi-wire branch circuits and two-wire 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. When more than one multi-wire branch circuit is carried through a single raceway the ungrounded conductors of the additional circuit may be of colors other those specified. All circuit conductors of the same color shall be connected to the same ungrounded feeder conductor throughout the installation. That makes my head spin. But, at least back then the color coding was all in one section. ![[Linked Image]](https://www.electrical-contractor.net/ubb/wink.gif)
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s-g — §2112 of the 1953 NECH seems to have the same wording as your 1959 verbiage, though I believe that by the 1971 edition specific multiwire color coding had been reduced to an unenforceable “suggestion”/fine-print note. In the 1953 book, I can’t locate any mention of high-leg identification/position in [Article 215] feeders or [Article 384] switchboards.
One thing to keep in mind is that 4-wire-delta feeders and panels are somewhat a modern implementation {40 years?} in electrical systems. At one time, for “240V” building services, 120/240v 1ø 3w and 240V 3ø 3w may have been routinely served from the same utility-owned transformer bank, but were ‘split’ at one end of the service drop, and separately metered typcially with “lighting” and “power” meters (usually under separate rates.) Remember that the 1ø 3w circuit would be a multiwire circuit, but the 3ø 3w circuit would not, so may not have had mandatory phase/color coding or uniform bus positions.
Where 3ø 3-wire boards, panels or gutters serving grouped fusible switches installed by qualified persons, there should have been no 'fourth-wire' grounded-circuit conductor to deal with. There would have been little chance for someone to inadvertently {or intentionally} make an ill-advised high-leg-to-neutral tap or similar potentially hazardous circuit configuration.
It took development and utility acceptance of [self-contained and transformer-rated] 4-wire-delta metering for highlegs and neutrals to “mix” and result in the need for a corresponding code revision.
[This message has been edited by Bjarney (edited 12-30-2004).]
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though I believe that by the 1971 edition specific multiwire color coding had been reduced to an unenforceable “suggestion”/fine-print note. Yep, I'm looking at the 1971 NEC now: 210-5(c) Ungrounded conductor. Where installed in raceways, as open work or 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.
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. There's a bar down the whole of 210-5(c), so something there was changed from the previous edition. Roger, SafetyGem, I should have mentioned that orange is mentioned in that 1971 code: 200-6(c) Where on a 4-wire delta-connected secondary, the midpoint of one phase is grounded to supply lighting and similar loads, that phase conductor having the higher voltage to ground shall be orange in color or be indicated by tagging or other effective means at any point where a connection is to be made if the neutral conductor is present. A bar indicating a revision extends across the two lines which I've highlighted above. Maybe this was the start of orange, unless something else was changed.
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Thank you for the Code, Curt! That's exactly what I wondered about. Very interesting! Sovereign San Francisco. (I couldn't find any Feng Shui ordinances, though) LA's Code no longer has the many amendments it used to. The copy I got was almost all administrative material. **************************************** When I started out the guy I worked for called 4W Delta system "Red Leg Deltas". He started in '54.
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