125 Amp Cable Size at 70 Meters (690V Three-Phase (Wind / Heavy Industrial))
IEC 60364-5-52 metric conductor sizing (mm²), voltage drop, and power loss calculation for 125 A over 70 m (229.7 ft).
Copper Cable (≤3% Drop)35 mm²Drop: 9.27V (1.34%)
Aluminum Cable (≤3% Drop)70 mm²Drop: 7.64V (1.11%)
Voltage at Load680.7 VLine Loss: 2006.2 W
Max Power & Breaker149.39 kW125A MCB/MCCB
IEC 60364 Cable Cross-Section Table (1.5 mm² – 400 mm²) for 125A at 70m
| 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 | 216.22 V (31.34%) | 473.8 V | 356.66 V (51.69%) | 46812.5 W | Drop High |
| 2.5 mm² | 24 A | 18 A | 129.73 V (18.8%) | 560.3 V | 213.99 V (31.01%) | 28087.5 W | Drop High |
| 4 mm² | 32 A | 25 A | 81.08 V (11.75%) | 608.9 V | 133.75 V (19.38%) | 17554.7 W | Drop High |
| 6 mm² | 41 A | 32 A | 54.05 V (7.83%) | 635.9 V | 89.16 V (12.92%) | 11703.1 W | Drop High |
| 10 mm² | 57 A | 44 A | 32.43 V (4.7%) | 657.6 V | 53.5 V (7.75%) | 7021.9 W | Drop High |
| 16 mm² | 76 A | 59 A | 20.27 V (2.94%) | 669.7 V | 33.44 V (4.85%) | 4388.7 W | Drop High |
| 25 mm² | 101 A | 78 A | 12.97 V (1.88%) | 677.0 V | 21.4 V (3.1%) | 2808.8 W | Drop High |
| 35 mm² | 125 A | 97 A | 9.27 V (1.34%) | 680.7 V | 15.29 V (2.22%) | 2006.2 W | ✓ OK (≤3%) |
| 50 mm² | 151 A | 118 A | 6.49 V (0.94%) | 683.5 V | 10.7 V (1.55%) | 1404.4 W | ✓ OK (≤3%) |
| 70 mm² | 192 A | 150 A | 4.63 V (0.67%) | 685.4 V | 7.64 V (1.11%) | 1003.1 W | ✓ OK (≤3%) |
| 95 mm² | 232 A | 181 A | 3.41 V (0.49%) | 686.6 V | 5.63 V (0.82%) | 739.1 W | ✓ OK (≤3%) |
| 120 mm² | 269 A | 210 A | 2.7 V (0.39%) | 687.3 V | 4.46 V (0.65%) | 585.2 W | ✓ OK (≤3%) |
| 150 mm² | 309 A | 241 A | 2.16 V (0.31%) | 687.8 V | 3.57 V (0.52%) | 468.1 W | ✓ OK (≤3%) |
| 185 mm² | 353 A | 275 A | 1.75 V (0.25%) | 688.2 V | 2.89 V (0.42%) | 379.6 W | ✓ OK (≤3%) |
| 240 mm² | 415 A | 324 A | 1.35 V (0.2%) | 688.6 V | 2.23 V (0.32%) | 292.6 W | ✓ OK (≤3%) |
| 300 mm² | 477 A | 372 A | 1.08 V (0.16%) | 688.9 V | 1.78 V (0.26%) | 234.1 W | ✓ OK (≤3%) |
| 400 mm² | 570 A | 445 A | 0.81 V (0.12%) | 689.2 V | 1.34 V (0.19%) | 175.5 W | ✓ OK (≤3%) |
FAQ — 125 Amp Cable Size at 70 Meters (690V Three-Phase (Wind / Heavy Industrial))
What mm² cable size is required for 125A at 70 meters (690V)?
According to IEC 60364-5-52 ampacity and the 3% maximum voltage drop standard, you need 35 mm² copper cable for 125A over 70m at 690V (voltage drop: 9.27V or 1.34%).
What is the power capacity of 125A at 690V?
At unity power factor, 125A at 690V supports 149.39 kW with a standard 125A circuit breaker.
Related Lengths & Currents (690V)
125A · 5m (690V)125A · 10m (690V)125A · 15m (690V)125A · 20m (690V)125A · 25m (690V)125A · 30m (690V)125A · 35m (690V)125A · 40m (690V)125A · 45m (690V)125A · 50m (690V)125A · 60m (690V)10A · 70m (690V)16A · 70m (690V)20A · 70m (690V)25A · 70m (690V)32A · 70m (690V)40A · 70m (690V)50A · 70m (690V)63A · 70m (690V)80A · 70m (690V)100A · 70m (690V)160A · 70m (690V)200A · 70m (690V)