Reference / Wire Colors
Quick reference · Grade G

Wire Colors

Conductor identification colors by country and system, separating code requirements from common convention.

Conductor colors 7 schemes

Region / systemPhasesNeutralProtective (ground)StatusPointer
United States — 208Y/120 V (convention)Black, Red, BlueWhite or grayGreen, green with yellow stripes, or bareNeutral and grounding colors are required; phase colors are industry convention, not a code requirement.NEC 200.6, 250.119, 210.5(C), 215.12(C)
United States — 480Y/277 V (convention)Brown, Orange, YellowGray (commonly), or whiteGreen, green with yellow stripes, or barePhase colors are convention. Where more than one system is present, the identification method must be posted.NEC 200.6, 210.5(C), 215.12(C)
United States — 4-wire delta high legHigh leg identified orangeWhite or grayGreen, green-yellow, or bareThe higher-voltage-to-ground conductor must be marked orange or otherwise identified.NEC 110.15, 230.56
CanadaRed, Black, BlueWhite or grayGreen or green-yellowPhase sequence colors for three-phase AC.CSA C22.1 (CEC) Rule 4-038
IEC / European Union / UK (since 2004–2006)L1 Brown, L2 Black, L3 GreyBlueGreen-and-yellowHarmonized colors.IEC 60445
United Kingdom (before 2004)Red, Yellow, BlueBlackGreen-and-yellowFound in existing installations; a warning notice is expected where old and new colors meet.BS 7671 (current edition)
South Korea (KEC, since 2021)L1 Brown, L2 Black, L3 GreyBlueGreen-and-yellowAligned with IEC. Older installations may use other colors.KEC 121.2

Own summary. Code clauses are pointers only. © RokBench.

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