ELECTRICAL DESIGN TOOLS

Voltage drop calculator

Check voltage drop, cable size or maximum distance.

AS/NZS 3008 · 2017

Calculation scope & engineering review

Uses documented AS/NZS 3008.1.1:2017 and AS/NZS 3008.1.1:2025 source data for supported calculations. Not independently verified by a licensed electrical engineer. Check results against the current published standards before use. New Zealand mode uses the 2017 Australian rating tables with New Zealand ambient conditions. Read assumptions and limitations.

Circuit requirements

Choose a calculation and enter your load

Choose what to calculate

Standard

Mode

Load

Phase

Voltage (V)

Rating

The entered power factor converts kW or hp to load current. Voltage drop uses the worst-case cable impedance for every rating unit.

Cable & route

Copper · multi-core · PVC · fixed 75°C

Cable and distance

Cable size (mm²)

Distance to load (m)

Copper, multi-core, PVC (V-90 75°C) only, at a fixed 75°C resistance — this quick tool doesn't ask for conductor material, insulation type or installation method. For those, use the Cable Size Calculator.

Results update when you calculate.