Electrical wiring color coding standard for three phase electrical applications are standardized to aid the identification of individual wire phases. Wiring color 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: ground wire, neutral wire, live wire, line 2 wire, line 3 electrical wire. This article details the following cable color codes:
- International Wiring Colors
- US Wiring Color Codes
- Old & New UK Wiring Colors
Fixed wiring electricity supply requires specific wiring color regulations (bs 7671) to identify different power lines in different countries. The USA has 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 has a different wiring color standard. The UK's new cable colors for plugs are now harmonized 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.
In the USA, color codes are usually utilized for power wires in “branch circuits,” the wiring between the last protective device.
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.
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
Green
White
Black
Red
Blue
Grey
Brown
Orange
Yellow
