Electrical Wire Color Codes (IEC, India, UK, US)
Choose a standard or region to see the colours for phase, neutral and protective earth conductors in three phase and single phase wiring.
Conductor colours
| Conductor | Colour |
|---|---|
| Phase L1 | Brown |
| Phase L2 | Black |
| Phase L3 | Grey |
| Neutral N | Blue |
| Protective earth PE | Green/Yellow |
Harmonised IEC Colours
IEC 60445 sets the identification of conductors by colour. For AC power it uses brown, black and grey for the three phases, blue for neutral and green/yellow only for protective earth.
Single phase circuits use brown for line, blue for neutral and green/yellow for earth.
Frequently Asked Questions
What is the IEC colour code for three phase wiring?
Brown (L1), black (L2), grey (L3), blue (neutral) and green/yellow (protective earth).
What colours are used in India?
Traditional Indian practice uses red, yellow and blue for the phases, black for neutral and green for earth. Many new projects follow the IEC colours; check the project specification.
Can green/yellow be used for anything other than earth?
No. Green/yellow is reserved exclusively for the protective conductor.
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