Wire Sizing Calculator

Free cable sizing tool based on IEC 60364-5-52. Calculate minimum cross-section, voltage drop, and derating factors for copper conductors.

⚡ Circuit Parameters

Per IEC 60364-5-52 Table B.52.1

Ref: IEC 60364-5-52 Table B.52.14

Ref: IEC 60364-5-52 Table B.52.17

📊 Results

Combined Derating Factor —

Temperature (Table B.52.14) × Grouping (Table B.52.17)

Required Current Capacity —

Breaker rating ÷ combined derating factor

Minimum Cross-Section —

Smallest standard size with sufficient capacity per Table B.52.2

Recommended Cross-Section —

Next size up for safety margin and voltage drop

Current Capacity (derated) —

Nominal capacity × derating factors

Voltage Drop —

ΔV = 2 × I × L × ρ / A (ρ = 0.0175 Ω·mm²/m for Cu at 20 °C)

Voltage Drop (%) —
Acceptable for Lighting (≤ 3%)? —
Acceptable for Other (≤ 5%)? —

IEC 60364-5-52 recommended voltage drop limits

Enter your circuit parameters and click Calculate to see results.

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