20 Amp Cable Size at 300 Meters (415V Three-Phase (UK / Australia Industrial))
IEC 60364-5-52 metric conductor sizing (mm²), voltage drop, and power loss calculation for 20 A over 300 m (984.3 ft).
Copper Cable (≤3% Drop)25 mm²Drop: 8.9V (2.14%)
Aluminum Cable (≤3% Drop)35 mm²Drop: 10.48V (2.53%)
Voltage at Load406.1 VLine Loss: 308.2 W
Max Power & Breaker14.38 kW20A MCB/MCCB
IEC 60364 Cable Cross-Section Table (1.5 mm² – 400 mm²) for 20A at 300m
| Cross-Section (mm²) | Cu Ampacity | Al Ampacity | Cu Voltage Drop | Load Voltage | Al Voltage Drop | Power Loss | Status |
|---|---|---|---|---|---|---|---|
| 1.5 mm² | 16 A | 12 A | 148.26 V (35.73%) | 266.7 V | 244.57 V (58.93%) | 5136.0 W | Drop High |
| 2.5 mm² | 24 A | 18 A | 88.96 V (21.44%) | 326.0 V | 146.74 V (35.36%) | 3081.6 W | Drop High |
| 4 mm² | 32 A | 25 A | 55.6 V (13.4%) | 359.4 V | 91.71 V (22.1%) | 1926.0 W | Drop High |
| 6 mm² | 41 A | 32 A | 37.07 V (8.93%) | 377.9 V | 61.14 V (14.73%) | 1284.0 W | Drop High |
| 10 mm² | 57 A | 44 A | 22.24 V (5.36%) | 392.8 V | 36.68 V (8.84%) | 770.4 W | Drop High |
| 16 mm² | 76 A | 59 A | 13.9 V (3.35%) | 401.1 V | 22.93 V (5.52%) | 481.5 W | ~ ≤5% |
| 25 mm² | 101 A | 78 A | 8.9 V (2.14%) | 406.1 V | 14.67 V (3.54%) | 308.2 W | ✓ OK (≤3%) |
| 35 mm² | 125 A | 97 A | 6.35 V (1.53%) | 408.6 V | 10.48 V (2.53%) | 220.1 W | ✓ OK (≤3%) |
| 50 mm² | 151 A | 118 A | 4.45 V (1.07%) | 410.6 V | 7.34 V (1.77%) | 154.1 W | ✓ OK (≤3%) |
| 70 mm² | 192 A | 150 A | 3.18 V (0.77%) | 411.8 V | 5.24 V (1.26%) | 110.1 W | ✓ OK (≤3%) |
| 95 mm² | 232 A | 181 A | 2.34 V (0.56%) | 412.7 V | 3.86 V (0.93%) | 81.1 W | ✓ OK (≤3%) |
| 120 mm² | 269 A | 210 A | 1.85 V (0.45%) | 413.1 V | 3.06 V (0.74%) | 64.2 W | ✓ OK (≤3%) |
| 150 mm² | 309 A | 241 A | 1.48 V (0.36%) | 413.5 V | 2.45 V (0.59%) | 51.4 W | ✓ OK (≤3%) |
| 185 mm² | 353 A | 275 A | 1.2 V (0.29%) | 413.8 V | 1.98 V (0.48%) | 41.6 W | ✓ OK (≤3%) |
| 240 mm² | 415 A | 324 A | 0.93 V (0.22%) | 414.1 V | 1.53 V (0.37%) | 32.1 W | ✓ OK (≤3%) |
| 300 mm² | 477 A | 372 A | 0.74 V (0.18%) | 414.3 V | 1.22 V (0.29%) | 25.7 W | ✓ OK (≤3%) |
| 400 mm² | 570 A | 445 A | 0.56 V (0.13%) | 414.4 V | 0.92 V (0.22%) | 19.3 W | ✓ OK (≤3%) |
FAQ — 20 Amp Cable Size at 300 Meters (415V Three-Phase (UK / Australia Industrial))
What mm² cable size is required for 20A at 300 meters (415V)?
According to IEC 60364-5-52 ampacity and the 3% maximum voltage drop standard, you need 25 mm² copper cable for 20A over 300m at 415V (voltage drop: 8.9V or 2.14%).
What is the power capacity of 20A at 415V?
At unity power factor, 20A at 415V supports 14.38 kW with a standard 20A circuit breaker.
Related Lengths & Currents (415V)
20A · 5m (415V)20A · 10m (415V)20A · 15m (415V)20A · 20m (415V)20A · 25m (415V)20A · 30m (415V)20A · 35m (415V)20A · 40m (415V)20A · 45m (415V)20A · 50m (415V)20A · 60m (415V)20A · 70m (415V)10A · 300m (415V)16A · 300m (415V)25A · 300m (415V)32A · 300m (415V)40A · 300m (415V)50A · 300m (415V)63A · 300m (415V)80A · 300m (415V)100A · 300m (415V)125A · 300m (415V)160A · 300m (415V)200A · 300m (415V)