n1ist;
I admire your ideas!
This is a really tough area as color codes can be so different per user area [Continentally Speaking
], and as far as being within the USA, the NEC does not specify the normal "Trade Common" color codes, so that could bring up arguments from certain "Hard-Heads"
If you do choose for Color codes, being "Trade Common" for the area of use would be a great idea!
For here in the "50 States", I could suggest the following:
<OL TYPE=1>
[*] 120/240 VAC 1 Phase 3 Wire: L1=Black, L2=Red, N=White, EGC=Green, IGC=Green w/Yellow stripes,
[*] 120/240 VAC 3 Phase 4 Wire (Delta): L1=Black, L2=Orange, L3=Blue, N=White, EGC=Green, IGC=Green w/yellow stripes,
[*] 120/208 3 Phase 4 Wire (Wye): L1=Black, L2=Red, L3=Blue, Common=White, EGC=Green, IGC=Green w/yellow stripes,
[*] 277/480 3 Phase 4 Wire (Wye): L1=Brown, L2=Orange (or Purple), L3=Yellow, Common=Gray, EGC=Green, IGC=Green w/yellow stripes,
[*] 120 VAC 1 Phase 2 Wire: L1=Black, N=White, EGC=Green, IGC=Green w/yellow stripe,
[*] 208 or 240 VAC 1 Phase 2 Wire: L1=Black, L2=Red, EGC=Green, IGC=Green w/yellow stripes,
[*] 277 VAC 1 phase 2 Wire: L1=Brown [or yellow], Common (N)=Gray, EGC=Green, IGC=Green w/yellow stripes,
[*] 208, 240, 480 or 600 VAC 3 Phase 3 Wire: L1=Black, L2=Red, L3=Blue, EGC=Green, IGC=Green w/yellow stripes.
[typical users would ID the 480 VAC Wye system with "B-O-Y", so that's another consideration].
</OL>
P.S. "EGC" is the Equipment Grounding Conductor and "IGC" is an Isolated Grounding Conductor.
If the cord has a White conductor which will be used for an Ungrounded Conductor, best if it's color was changed to something else [like blue or red], so it doesn't confused the installer.
Need some input from the European sector
[Paging Pauluk! Please pick up the White Courtesy Phone!
]
Good luck!
Scott S.E.T.