Wiring color: red instead of black OK?

Bear in mind the NEC is not a design manual. Proper conductor management is crucial but that is not defined in the NEC.

Typically the convention is 120/208 wye will be black/red/blue with a white neutral.

480 wye will be Brown,/Orange/Yellow with violet/gray for the 277 line to neutral

The rub comes in when you have 240 center tapped delta because then the code requires orange be used for the 208 leg. If this was also in a building with 480 you could have some confusion. In real life I have never seen them together. Typically 240 delta is only in a light industrial area where they are trying to save money (2 transformers) or where they really want 240v 3p. The only place I have ever seen delta with 3 transformers is behind the Hog's Breath Saloon in Key West (look up at the pole behind the outside stage). I bet they just "grew" into that situation

Reply to
gfretwell
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You are right. If there are different voltage systems in the same building (not just the same conduit) the NEC requires an identification scheme. The scheme has to be readily available, which may be by posting on the panels. Requirements have tightened over the last few code cycles.

Schemes I have seen are the same as what gfretwell posted.

Reply to
bud--

Those have become so much of a national standard that AFC is selling MC cable with those mixes and the colors painted on the jacket for instant ID. It makes it real easy for inspectors and maintainers to figure out what the installer was doing.

Reply to
gfretwell

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