Cable Size Calculation - Electrical

Vd per km for 10 mm² copper (from table) ≈ 3.8 V/A/km (3-phase) Vd = 3.8 × 51 × 0.15 = %Vd = 29.1 / 400 = 7.3% – exceeds 5% limit → increase size .

Example: Load = 50 A, ambient 45°C (correction factor 0.82 for 90°C insulation), 4 cables together (grouping 0.80) → 50 / (0.82 × 0.80) = Step 3: Select Initial Cable Size from Ampacity Table From standard tables (e.g., IEC 60364 or NEC Table 310.16), choose a cable with ampacity ≥ calculated value. electrical cable size calculation

10 mm² → 72 A → meets 66.4 A requirement. Vd per km for 10 mm² copper (from table) ≈ 3