Electrical Cable Size Calculations ((hot)) May 2026

| Factor | Condition | Typical value | |--------|-----------|----------------| | k₁ – Ambient temp | 40°C (IEC) | 0.87 (PVC) | | k₂ – Grouping | 4 cables touching | 0.70 | | k₃ – Thermal insulation | Buried or in insulation | 0.70–0.85 | | k₄ – Altitude (>2000m) | 3000m | ~0.93 |

Common factors:

L=80m, I=24.5A, mV/A/m=7.3 [ VD = \frac7.3 \times 24.5 \times 801000 = 14.3 V ] Percentage = (14.3 / 415 = 3.45%) → OK (<5%). electrical cable size calculations