Articles

Conductor Resistance & Temperature Calculator

Resistance at temperature

0.0446 Ω

Resistance at temperature

0.0438 Ω

Resistance at 20°C

How this calculator works

How to use the Conductor Resistance & Temperature Calculator

The Formula

R(T) = R₂₀ × [1 + α(T − 20°C)] where R₂₀ = ρL/A. Copper ρ ≈ 0.0175 Ω·mm²/m; aluminum ρ ≈ 0.0282 Ω·mm²/m at 20°C.

Practical Example

Hot conductors increase I²R loss and voltage drop. Size cables using field temperature—not datasheet 25°C values—before quoting wire quantities.

About Conductor Resistance & Temperature Calculator

Temperature-adjusted resistance

R(T) = R₂₀ × [1 + α(T − 20°C)] where R₂₀ = ρL/A. Copper ρ ≈ 0.0175 Ω·mm²/m; aluminum ρ ≈ 0.0282 Ω·mm²/m at 20°C.

Why it matters for DC cable BOM

Hot conductors increase I²R loss and voltage drop. Size cables using field temperature—not datasheet 25°C values—before quoting wire quantities.