The colour of a conductor's insulation tells you what it is meant to be. AS/NZS 3000 sets the colours for fixed installation wiring, and AS/NZS 3760 gives the colours of flexible cords. This page sets them out for New Zealand and Australia, with the colours older work still carries.
Fixed wiring
| Function | Colour |
|---|---|
| Protective earth | Green/yellow |
| Equipotential bonding | Green/yellow |
| Neutral | Black or light blue |
| Active | Any colour other than green, yellow, green/yellow, black or light blue |
- New Zealand homes. In a domestic installation the neutral is black only (Table 3.4 Note 4).
- Recommended actives. Red or brown for a single‑phase active; red, white or blue for the actives of a multiphase circuit. These are recommendations. The table sets no phase order.
- Never live. Green, yellow and green/yellow are never an active or a neutral in installation wiring (Cl 3.8.1).
- No mixing. Australian and New Zealand colours and European colours do not go in one enclosure or one multicore cable.
Older installations
An installation wired to a previous edition may carry:
- a bare or green earthing or bonding conductor, which may stay; a new termination on it is sleeved green/yellow (Cl 3.8.2.2);
- a yellow live conductor, which may stay; a new termination on it is sleeved white (Cl 3.8.2.3).
Sleeving can also mark a black or light blue conductor as an active, or another colour as a neutral, at each termination. It never turns a green, yellow or green/yellow conductor into either.
Flexible cords
| Function | Modern cord | Superseded cord |
|---|---|---|
| Active | Brown | Red |
| Neutral | Light blue | Black |
| Earth | Green/yellow | Green |
A modern three‑phase cord has brown, black and grey phases, a blue neutral where it has one, and a green/yellow earth on Class I equipment. A Class II cord has no earth. Old and imported cord sets may follow neither scheme.
Before you trust a colour
A colour is what the installer meant. Prove a conductor dead and prove what it is by test before you work on it.
Look up a colour, or the colours of a circuit, with the conductor colour lookup. A worked older house is in Reading the wiring in an older house.