Colour codes USA 3 phase ?
Colour codes USA 3 phase ?
(OP)
I would like to know the colour codes for USA wiring 3 phase ?
David Gowland
David Gowland
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Colour codes USA 3 phase ?
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RE: Colour codes USA 3 phase ?
For 208/120V systems: Black, Red, Blue for A,B,C phases
For 480/277V systems: Brown, Orange, Yellow for A,B,C phases
Mike
RE: Colour codes USA 3 phase ?
But beware, there is no single "standard" published in any code in the US for phase insulation colors (NEC does have specific requirements for neutral & ground insulation colors). And there are many conflicting color codes in use.
One notable exception is the Dept. of Energy, where they use Red-Blue-Black for ABC for both 208 & 480 volt systems.
RE: Colour codes USA 3 phase ?
Many thanks,
I have another question , but that may have been answered by the reply ,some American households have two phases , for 240v across the phases and a neutral. If the normal code is black for phase and white for neutral what colour is used for the other phase ?
regards David
Orchard Electronic
Hailsham
E.Sussex
RE: Colour codes USA 3 phase ?
Blacksmith
RE: Colour codes USA 3 phase ?
I second peebee's admonition that there is no universal standard in the US for phase colors on three phase systems.
RE: Colour codes USA 3 phase ?
The phases can be any color you please so long is it's not white, gray, or green.
There's lots of houses wired with all hot wires black. There's plenty of houses wired with all the colors of the rainbow, too.
RE: Colour codes USA 3 phase ?
For 208/120V systems: Black, Red, Blue for A,B,C phases
For 480/277V systems: Brown, Orange, Yellow for A,B,C phases
No code for most conductors except ground, neutral (as stated) and then some other "oddball" applications.
For an isolated power system in a health care facility, orange, brown and yellow are required for the isolated conductors. Article 517
110.15 High-Leg Marking.
On a 4-wire, delta-connected system where the midpoint of one phase winding is grounded to supply lighting and similar loads, the conductor or busbar having the higher phase voltage to ground shall be durably and permanently marked by an outer finish that is orange in color or by other effective means.
424.35 Marking of Heating Cables.
Each unit shall be marked with the identifying name or identification symbol, catalog number, and ratings in volts and watts or in volts and amperes.
Each unit length of heating cable shall have a permanent legible marking on each nonheating lead located within 75 mm (3 in.) of the terminal end. The lead wire shall have the following color identification to indicate the circuit voltage on which it is to be used:
(1) 120 volt, nominal — yellow
(2) 208 volt, nominal — blue
(3) 240 volt, nominal — red
(4) 277 volt, nominal — brown
(5) 480 volt, nominal — orange