Inputs

Nominal voltage V Enter a numeric project value in V at or above 1. Load current A Enter a numeric project value in A at or above 0.01. One-way length m Enter a numeric project value in m at or above 0.1. Conductor area mm2 Enter a numeric project value in mm2 at or above 0.1. Conductor resistivity ohm mm2/m Enter a numeric project value in ohm mm2/m at or above 0.001. Current-carrying conductor count Enter a numeric project value between 1 and 4.

Voltage drop -- V

Voltage drop percentage -- %

Estimated end voltage -- V

Loop resistance -- ohm

Calculation details

Voltage drop: -- V
Voltage drop percentage: -- %
Estimated end voltage: -- V
Loop resistance: -- ohm

Important notes

The one-way length convention must be recorded so both conductors are included consistently.
Cable selection, protection, thermal derating, and Australian wiring requirements require licensed review.

Formulas

\(\displaystyle R_{\mathrm{loop}} = \rho \frac{L_{\mathrm{one-way}}N}{A}\)
\(\displaystyle V_{\mathrm{drop}} = IR_{\mathrm{loop}}\)
Use the actual installation topology and temperature conditions; this is not a cable selection certificate.

Estimate loop resistance, voltage drop, and end voltage for a lighting cable run.

Lighting Cable Length and Voltage Drop Calculator is a planning aid. Keep the target source, product data, measurement method, and project assumptions with the result. Confirm compliance, installation, certification, and safety decisions with the responsible professional.

Inputs

Results

Formulas