210.5(C)

[ryan_618]

Add exception at the end of the existing section, as follows:

210.5 Identification for Branch Circuits.
(C)Ungrounded Conductors. Where the premises wiring system has branch circuits supplied from more than one nominal voltage system, each ungrounded conductor of a branch circuit, where accessible, shall be identified by system. The means of identification shall be permitted to be by separate color coding, marking tape, tagging, or other approved means and shall be permanently posted at each branch-circuit panelboard or similar branch-circuit distribution equipment.
Exception: Installations complying with 517.160(A)(5) shall not be required to be distinguished from other voltage systems.


Substantiation: Brown, Orange and Yellow has been an unofficial (and not required) means of identifying 480Y/277 volt systems for many, many years. In order to comply with the above section in a health facility that employs isolated power systems, the 480Y/277 volt system would have to be identified in a different manner that could perhaps injure installers and or maintenance personnel that have used this coloring scheme for many years (without incident).

 

[George Stolz]

Re: 210.5(C)

I thought that the conductors would be marked twice in those installations: BOY towards the terminations, and a separate color code (Say, blue for the "Blue" panel) on each conductor.

I've never seen an SDS in the flesh, but in reading this is what I have assumed I would see.

(Again, I'm totally unqualified to respond to this. )
Edit:

[ June 27, 2005, 11:32 PM: Message edited by: georgestolz ]