DC Wire Gauge & Voltage Drop Calculator

Compute cable resistance, % drop & conductor loss

Calculate exact DC voltage drop across copper cable runs between your solar array, charge controller, battery bank, and inverter.

Calculations based on NEC Chapter 9 Table 8 standard annealed copper resistance at 75°C. Critical solar wiring should always stay below 2% voltage drop.

This free calculator runs in your browser. See all calculators.