Estimate a conductor cross-section from current and voltage drop before checking the applicable wiring rules, installation method and protective device.
Electrical & cable sizing ↗Voltage-drop estimate only. It does not verify current-carrying capacity, installation method, ambient temperature, grouping, fault protection, power factor/reactance or compliance with local wiring rules. Use a qualified electrical designer or electrician for final cable selection.
Estimated conductor area = circuit factor × resistivity × one-way length × current ÷ allowed voltage drop. The result is rounded up to the next common conductor size.
Reference values for sizing. Manufacturer ranges, tolerances and standard variants can differ; verify the product datasheet before ordering.