Physical Address
304 North Cardinal St.
Dorchester Center, MA 02124
IEC 60304: Low-Frequency Cable Insulation Colours — The “Universal Language” of Electrical Wiring
Yellow-Green=Earth, Blue=Neutral — How Wire Colour Coding Became a Global Standard
IEC 60304:1982 specifies low-frequency cable and wire insulation colour standard sequences. Yellow-Green (PE protective earth), Blue (N neutral), Brown/Black/Grey (L1/L2/L3 phases) — this colour code is the electrical installation “universal language.”
TNLab — Wire colour coding is the simplest yet most life-critical standardization in electrical engineering.
