Electrical Wiring Colors

Wiring Colors | Electrical Wire Color Coding Standards

Electrical wiring color coding standard for three phase electrical applications are standardised to aid the identification of individual wire phases. Wiring colour codes for AC and DC power distribution circuits have changed on numerous occasions and vary depending on region. For three phase electricity supply, circuits will use five wires: earth wire, neutral wire, live wire, line 2 wire, line 3 electrical wire. This article details the following cable colour codes:

- International Wiring Colors
- US Wiring Color Codes
- Old & New UK Wiring Colors

International Wiring Color Codes

Fixed wiring electricity supply requires specific wiring colour regulations (bs 7671) to identify different power lines in different countries. The USA have their own wiring colors for electrical circuits, black, red, and blue are used for 208 VAC three-phase; brown, orange and yellow are used for 480 VAC. Australia also have a different wiring colour standard. The UK's new cable colors for plugs are now harmonise with Europe's power cable colors for AC & DC. Most of Europe abides by IEC ('International Electrotechnical Commission') electrical wiring colors code for AC branch circuits.
RegionEarth (E)Neutral (N)Line 1 (L1)Line 2 (L2)Line 3 (L3)
Europe & UKGreen Earth Wiring ColoursGreenBlue Neutral Wire Wiring Colour CodeBlueBrown Wire Wiring Colour CodeBrownBlack Wire Wiring EU UK Colour CodeBlackGrey Wire Wiring Colours UK EUGrey
UK (Old)Green Earth Wiring ColoursGreenBlack Wire Wiring Colours UK OldBlackRed Old UK Live Wire ColourRedYellow Cable Colour CodeYellowBlue Neutral Wire Wiring Colour CodeBlue
AustraliaGreen Earth Wiring ColoursGreenBlack Wire Wiring Colour CodingBlackRed Wire Wiring Colour CodingRedWhite Wire Wiring Colour Coding Australia CodeWhiteBlue Wire Wiring Colour CodeBlue
USAGreen Earth Wiring ColoursGreenWhite Usa Neutral Wire Wiring Colour CodingWhiteBlack Wire Wiring Colours CodingBlackRed Wire Wiring Colours CodingRedBlue Wire Wiring Colour CodeBlue

US Wiring Color Codes

In the USA, color codes are usually utilized for power wires in “branch circuits,” the wiring between the last protective device.

AC Wire Colors For 120/208/240 Volts

These are the types of wire colors commonly found in home and office settings. 

Phase 1 - Black 

Phase 2 - Red 

Phase 3 - Blue Neutral - White Ground - Green, Green with Yellow Stripe, or Bare Wire

If one phase of your wiring is at a higher voltage than others, using a high-leg connection, wires should be marked orange for that phase. High-leg connections are typically uncommon in newer installations.

AC Wire Colors For 277/480 Volt

Industrial motors and equipment typically have higher voltage systems. Phase 1 - Brown Phase 2 - Orange Phase 3 - Yellow Neutral - Gray Ground - Green, Green with Yellow Stripe, or Bare Wire

It is very important to have a documented wire labeling system for higher voltage systems. Labels should include information regarding the circuit, and the appropriate disconnection point for lockout/tagout.

Wire Colors for DC Power

DC or Direct Current, is typically used in battery systems and solar power systems, instead of AC or Alternating Current. Positive (non-ground) - Red Negative (non-ground) - Black Ground - White or Gray

Europe & New UK Three Phase Power Cable Colors

Power cables in Europe and the UK are identified through standardised power cable colour coding.
CableEarth (E)Neutral (N)Live 1 (L1)Line 2 (L2)Line 3 (L3)
ColourGreen Earth Wiring ColoursGreenBlue Neutral Wire Wiring Colour CodeBlueBrown Live Wire EU Wiring ColoursBrownBlack Line 2 Wire Colour EU UKBlackGrey Wiring Colours UK EUGrey
© 2019 Phase 3 USA | Industrial Power Connectors
Designed and Powered by PageNorth Digital