Pro Tip: If your run is over 100 meters, (e.g., from 2.5mm² to 6mm²) rather than one. 3 Critical Mistakes Aussies Make 1. Forgetting the Return Path When using a calculator, do you double the distance? Yes. The current travels down the active AND back the neutral. If your shed is 50m from the switchboard, the total circuit length is 100m . Most good calculators ask for "One-way distance" and do this math for you.
| Cable Size (mm²) | Max run for 10A (230V) @ 5% | Max run for 20A (230V) @ 5% | | :--- | :--- | :--- | | | 35 meters | Not recommended | | 2.5mm² | 58 meters | 29 meters | | 4mm² | 93 meters | 46 meters | | 6mm² | 140 meters | 70 meters | voltage drop calculator australia
Example: A 20A circuit, 50 meters away, using 2.5mm² cable. (50 x 20 x 0.017) / 2.5 = 6.8 Volts lost. (6.8V / 230V = 2.9% drop – acceptable for general use). Pro Tip: If your run is over 100 meters, (e