As I read the code, orange is really only a
suggested color for the high-leg on a 4w delta, not mandatory (my emphasis added):
215.8 Means of Identifying Conductor with the Higher Voltage to Ground. On a 4-wire delta-connected secondary where the midpoint of one phase winding is grounded to supply lighting and similar loads, the phase conductor having the higher voltage to ground shall be identified by an outer finish that is orange in color or by tagging or other effective means. Such identification shall be placed at each point where a connection is made if the grounded conductor is also present.
The 1971 NEC says the same thing in article 200-6(c), just with slightly different wording, but has a bar indicating a change beside the part which mentions orange or other effective means. Could this be when the orange high-leg was added to the code?
You could mark all three conductors orange in a midpoint-grounded delta system. It just wouldn't be very helpful.
I can't find anything in the 2002 code against doing that, but it seems as though it would have been a violation at one time. 1971 NEC, article 210-15(c), emphasis added again:
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.
There is then a
recommendation that basic circuits for a single wiring system use black, black/red, or black/red/blue as phases.
This whole article is marked as changed from the previous edition.
[This message has been edited by pauluk (edited 11-06-2005).]
