125 Amp Cable Size at 250 Meters (415V Three-Phase (UK / Australia Industrial))
IEC 60364-5-52 metric conductor sizing (mm²), voltage drop, and power loss calculation for 125 A over 250 m (820.2 ft).
Copper Cable (≤3% Drop)95 mm²Drop: 12.19V (2.94%)
Aluminum Cable (≤3% Drop)185 mm²Drop: 10.33V (2.49%)
Voltage at Load402.8 VLine Loss: 2639.8 W
Max Power & Breaker89.85 kW125A MCB/MCCB
IEC 60364 Cable Cross-Section Table (1.5 mm² – 400 mm²) for 125A at 250m
| 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 | 772.21 V (186.07%) | 0.0 V | 1273.78 V (306.93%) | 167187.5 W | Drop High |
| 2.5 mm² | 24 A | 18 A | 463.32 V (111.64%) | 0.0 V | 764.27 V (184.16%) | 100312.5 W | Drop High |
| 4 mm² | 32 A | 25 A | 289.58 V (69.78%) | 125.4 V | 477.67 V (115.1%) | 62695.3 W | Drop High |
| 6 mm² | 41 A | 32 A | 193.05 V (46.52%) | 221.9 V | 318.44 V (76.73%) | 41796.9 W | Drop High |
| 10 mm² | 57 A | 44 A | 115.83 V (27.91%) | 299.2 V | 191.07 V (46.04%) | 25078.1 W | Drop High |
| 16 mm² | 76 A | 59 A | 72.39 V (17.44%) | 342.6 V | 119.42 V (28.78%) | 15673.8 W | Drop High |
| 25 mm² | 101 A | 78 A | 46.33 V (11.16%) | 368.7 V | 76.43 V (18.42%) | 10031.2 W | Drop High |
| 35 mm² | 125 A | 97 A | 33.09 V (7.97%) | 381.9 V | 54.59 V (13.15%) | 7165.2 W | Drop High |
| 50 mm² | 151 A | 118 A | 23.17 V (5.58%) | 391.8 V | 38.21 V (9.21%) | 5015.6 W | Drop High |
| 70 mm² | 192 A | 150 A | 16.55 V (3.99%) | 398.5 V | 27.3 V (6.58%) | 3582.6 W | ~ ≤5% |
| 95 mm² | 232 A | 181 A | 12.19 V (2.94%) | 402.8 V | 20.11 V (4.85%) | 2639.8 W | ✓ OK (≤3%) |
| 120 mm² | 269 A | 210 A | 9.65 V (2.33%) | 405.3 V | 15.92 V (3.84%) | 2089.8 W | ✓ OK (≤3%) |
| 150 mm² | 309 A | 241 A | 7.72 V (1.86%) | 407.3 V | 12.74 V (3.07%) | 1671.9 W | ✓ OK (≤3%) |
| 185 mm² | 353 A | 275 A | 6.26 V (1.51%) | 408.7 V | 10.33 V (2.49%) | 1355.6 W | ✓ OK (≤3%) |
| 240 mm² | 415 A | 324 A | 4.83 V (1.16%) | 410.2 V | 7.96 V (1.92%) | 1044.9 W | ✓ OK (≤3%) |
| 300 mm² | 477 A | 372 A | 3.86 V (0.93%) | 411.1 V | 6.37 V (1.53%) | 835.9 W | ✓ OK (≤3%) |
| 400 mm² | 570 A | 445 A | 2.9 V (0.7%) | 412.1 V | 4.78 V (1.15%) | 627.0 W | ✓ OK (≤3%) |
FAQ — 125 Amp Cable Size at 250 Meters (415V Three-Phase (UK / Australia Industrial))
What mm² cable size is required for 125A at 250 meters (415V)?
According to IEC 60364-5-52 ampacity and the 3% maximum voltage drop standard, you need 95 mm² copper cable for 125A over 250m at 415V (voltage drop: 12.19V or 2.94%).
What is the power capacity of 125A at 415V?
At unity power factor, 125A at 415V supports 89.85 kW with a standard 125A circuit breaker.
Related Lengths & Currents (415V)
125A · 5m (415V)125A · 10m (415V)125A · 15m (415V)125A · 20m (415V)125A · 25m (415V)125A · 30m (415V)125A · 35m (415V)125A · 40m (415V)125A · 45m (415V)125A · 50m (415V)125A · 60m (415V)125A · 70m (415V)10A · 250m (415V)16A · 250m (415V)20A · 250m (415V)25A · 250m (415V)32A · 250m (415V)40A · 250m (415V)50A · 250m (415V)63A · 250m (415V)80A · 250m (415V)100A · 250m (415V)160A · 250m (415V)200A · 250m (415V)