125 Amp Cable Size at 15 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 15 m (49.2 ft).
Copper Cable (≤3% Drop)35 mm²Drop: 1.99V (0.29%)
Aluminum Cable (≤3% Drop)70 mm²Drop: 1.64V (0.24%)
Voltage at Load688.0 VLine Loss: 429.9 W
Max Power & Breaker149.39 kW125A MCB/MCCB
IEC 60364 Cable Cross-Section Table (1.5 mm² – 400 mm²) for 125A at 15m
| 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 | 46.33 V (6.71%) | 643.7 V | 76.43 V (11.08%) | 10031.2 W | Drop High |
| 2.5 mm² | 24 A | 18 A | 27.8 V (4.03%) | 662.2 V | 45.86 V (6.65%) | 6018.8 W | Drop High |
| 4 mm² | 32 A | 25 A | 17.37 V (2.52%) | 672.6 V | 28.66 V (4.15%) | 3761.7 W | Drop High |
| 6 mm² | 41 A | 32 A | 11.58 V (1.68%) | 678.4 V | 19.11 V (2.77%) | 2507.8 W | Drop High |
| 10 mm² | 57 A | 44 A | 6.95 V (1.01%) | 683.1 V | 11.46 V (1.66%) | 1504.7 W | Drop High |
| 16 mm² | 76 A | 59 A | 4.34 V (0.63%) | 685.7 V | 7.17 V (1.04%) | 940.4 W | Drop High |
| 25 mm² | 101 A | 78 A | 2.78 V (0.4%) | 687.2 V | 4.59 V (0.66%) | 601.9 W | Drop High |
| 35 mm² | 125 A | 97 A | 1.99 V (0.29%) | 688.0 V | 3.28 V (0.47%) | 429.9 W | ✓ OK (≤3%) |
| 50 mm² | 151 A | 118 A | 1.39 V (0.2%) | 688.6 V | 2.29 V (0.33%) | 300.9 W | ✓ OK (≤3%) |
| 70 mm² | 192 A | 150 A | 0.99 V (0.14%) | 689.0 V | 1.64 V (0.24%) | 215.0 W | ✓ OK (≤3%) |
| 95 mm² | 232 A | 181 A | 0.73 V (0.11%) | 689.3 V | 1.21 V (0.17%) | 158.4 W | ✓ OK (≤3%) |
| 120 mm² | 269 A | 210 A | 0.58 V (0.08%) | 689.4 V | 0.96 V (0.14%) | 125.4 W | ✓ OK (≤3%) |
| 150 mm² | 309 A | 241 A | 0.46 V (0.07%) | 689.5 V | 0.76 V (0.11%) | 100.3 W | ✓ OK (≤3%) |
| 185 mm² | 353 A | 275 A | 0.38 V (0.05%) | 689.6 V | 0.62 V (0.09%) | 81.3 W | ✓ OK (≤3%) |
| 240 mm² | 415 A | 324 A | 0.29 V (0.04%) | 689.7 V | 0.48 V (0.07%) | 62.7 W | ✓ OK (≤3%) |
| 300 mm² | 477 A | 372 A | 0.23 V (0.03%) | 689.8 V | 0.38 V (0.06%) | 50.2 W | ✓ OK (≤3%) |
| 400 mm² | 570 A | 445 A | 0.17 V (0.03%) | 689.8 V | 0.29 V (0.04%) | 37.6 W | ✓ OK (≤3%) |
FAQ — 125 Amp Cable Size at 15 Meters (690V Three-Phase (Wind / Heavy Industrial))
What mm² cable size is required for 125A at 15 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 15m at 690V (voltage drop: 1.99V or 0.29%).
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 · 20m (690V)125A · 25m (690V)125A · 30m (690V)125A · 35m (690V)125A · 40m (690V)125A · 45m (690V)125A · 50m (690V)125A · 60m (690V)125A · 70m (690V)10A · 15m (690V)16A · 15m (690V)20A · 15m (690V)25A · 15m (690V)32A · 15m (690V)40A · 15m (690V)50A · 15m (690V)63A · 15m (690V)80A · 15m (690V)100A · 15m (690V)160A · 15m (690V)200A · 15m (690V)