Cable Sizes Australia ((full)) May 2026

If you are wiring a shed, installing a new air conditioner, or simply replacing a power point, understanding cable sizes is critical. In Australia, using the wrong cable size isn't just inefficient—it is a fire hazard and a breach of the Wiring Rules (AS/NZS 3000).

Here is everything you need to know about choosing the correct cable size for your job. In Australia, we use the metric system for cross-sectional area (mm²). A common mistake is thinking "thicker wire is always better." While thicker wire reduces resistance, it is more expensive and harder to terminate. cable sizes australia

Voltage drop between the point of supply and the equipment must not exceed 5% for general power (230V → 218.5V) or 8% for lighting (230V → 211.6V). If you are wiring a shed, installing a

This guide is for educational purposes and does not replace a site-specific calculation by a qualified professional. Disclaimer: This information is based on general AS/NZS 3008 guidelines as of 2025. Actual installation depends on derating factors, insulation types, and specific site conditions. Hire a licensed professional. In Australia, we use the metric system for