IEC 60757 Wire Color Codes
The international standard for electrical conductor color coding used throughout Europe and globally.
What is IEC 60757?
IEC 60757 is the International Electrotechnical Commission standard for color coding of electrical conductors. It defines two-letter abbreviations (BK, BN, RD, etc.) for wire identification and is the basis for electrical wiring standards in Europe, Asia, and most countries outside North America.
Two-Letter Color Abbreviations
IEC 60757 uses standardized two-letter codes for international consistency:
IEC 60757 Color Chart
| Color | Code | Function | Usage |
|---|---|---|---|
Black | BK | Phase (L3) | Line conductor, phase wire in 3-phase systems |
Brown | BN | Phase (L1) | Live/hot conductor, single-phase line |
Red | RD | Positive DC | Positive DC supply, fire alarm circuits |
Orange | OG | Alarm | Alarm circuits, interlocks, control |
Yellow | YE | Control | Control circuits (with green = PE/ground) |
Green | GN | Earth (PE) | Protective earth, ground (always with yellow) |
Blue | BU | Neutral (N) | Neutral conductor, negative DC |
Violet | VT | ELV | Extra-low voltage systems, special circuits |
Gray | GY | Phase (L2) | Line conductor in 3-phase, data lines |
White | WH | Neutral/Return | Neutral, signal return, secondary |
Pink | PK | Special | Specific equipment circuits |
Turquoise | TQ | Data | Data transmission, communication |
Green-Yellow | GNYE | Earth (PE) | Protective earth/ground conductor (mandatory) |
European 3-Phase Wiring (400V)
Phase Conductors
- L1 (Brown) - Phase 1
- L2 (Gray) - Phase 2
- L3 (Black) - Phase 3
Neutral & Earth
- N (Blue) - Neutral
- PE (Green-Yellow) - Earth
Important: Green-Yellow (GNYE) is exclusively reserved for protective earth (PE). Never use green or yellow alone for other circuits in IEC-compliant installations.
DC Power Systems
Positive Supply
DC positive (+)
Negative Supply
DC negative (-)
Related Standards
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