The following wiring colours are used for BS7671. The changes were made as a result of international standardisation (or harmonisation) with most of Europe already using this colour coding, the new colours are sometimes referred to as ‘harmonised’.
UK Single Phase Wiring
- Line = Brown
- Neutral = Blue
- Earth = Green / Yellow
UK Three Phase Wiring
- Line L1 = Brown
- Line L2 = Black
- Line L3 = Grey
- Neutral = Blue
- Earth = Green / Yellow
