70 Amp Cable Size at 120 Meters (690V Three-Phase (Wind / Heavy Industrial))
IEC 60364-5-52 metric conductor sizing (mm²), voltage drop, and power loss calculation for 70 A over 120 m (393.7 ft).
Copper Cable (≤3% Drop)16 mm²Drop: 19.46V (2.82%)
Aluminum Cable (≤3% Drop)25 mm²Drop: 20.54V (2.98%)
Voltage at Load670.5 VLine Loss: 2359.3 W
Max Power & Breaker83.66 kW70A MCB/MCCB
IEC 60364 Cable Cross-Section Table (1.5 mm² – 400 mm²) for 70A at 120m
| 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 | 207.57 V (30.08%) | 482.4 V | 342.39 V (49.62%) | 25166.4 W | Drop High |
| 2.5 mm² | 24 A | 18 A | 124.54 V (18.05%) | 565.5 V | 205.44 V (29.77%) | 15099.8 W | Drop High |
| 4 mm² | 32 A | 25 A | 77.84 V (11.28%) | 612.2 V | 128.4 V (18.61%) | 9437.4 W | Drop High |
| 6 mm² | 41 A | 32 A | 51.89 V (7.52%) | 638.1 V | 85.6 V (12.41%) | 6291.6 W | Drop High |
| 10 mm² | 57 A | 44 A | 31.14 V (4.51%) | 658.9 V | 51.36 V (7.44%) | 3775.0 W | Drop High |
| 16 mm² | 76 A | 59 A | 19.46 V (2.82%) | 670.5 V | 32.1 V (4.65%) | 2359.3 W | ✓ OK (≤3%) |
| 25 mm² | 101 A | 78 A | 12.45 V (1.8%) | 677.5 V | 20.54 V (2.98%) | 1510.0 W | ✓ OK (≤3%) |
| 35 mm² | 125 A | 97 A | 8.9 V (1.29%) | 681.1 V | 14.67 V (2.13%) | 1078.6 W | ✓ OK (≤3%) |
| 50 mm² | 151 A | 118 A | 6.23 V (0.9%) | 683.8 V | 10.27 V (1.49%) | 755.0 W | ✓ OK (≤3%) |
| 70 mm² | 192 A | 150 A | 4.45 V (0.64%) | 685.6 V | 7.34 V (1.06%) | 539.3 W | ✓ OK (≤3%) |
| 95 mm² | 232 A | 181 A | 3.28 V (0.47%) | 686.7 V | 5.41 V (0.78%) | 397.4 W | ✓ OK (≤3%) |
| 120 mm² | 269 A | 210 A | 2.59 V (0.38%) | 687.4 V | 4.28 V (0.62%) | 314.6 W | ✓ OK (≤3%) |
| 150 mm² | 309 A | 241 A | 2.08 V (0.3%) | 687.9 V | 3.42 V (0.5%) | 251.7 W | ✓ OK (≤3%) |
| 185 mm² | 353 A | 275 A | 1.68 V (0.24%) | 688.3 V | 2.78 V (0.4%) | 204.1 W | ✓ OK (≤3%) |
| 240 mm² | 415 A | 324 A | 1.3 V (0.19%) | 688.7 V | 2.14 V (0.31%) | 157.3 W | ✓ OK (≤3%) |
| 300 mm² | 477 A | 372 A | 1.04 V (0.15%) | 689.0 V | 1.71 V (0.25%) | 125.8 W | ✓ OK (≤3%) |
| 400 mm² | 570 A | 445 A | 0.78 V (0.11%) | 689.2 V | 1.28 V (0.19%) | 94.4 W | ✓ OK (≤3%) |
FAQ — 70 Amp Cable Size at 120 Meters (690V Three-Phase (Wind / Heavy Industrial))
What mm² cable size is required for 70A at 120 meters (690V)?
According to IEC 60364-5-52 ampacity and the 3% maximum voltage drop standard, you need 16 mm² copper cable for 70A over 120m at 690V (voltage drop: 19.46V or 2.82%).
What is the power capacity of 70A at 690V?
At unity power factor, 70A at 690V supports 83.66 kW with a standard 70A circuit breaker.
Related Lengths & Currents (690V)
70A · 5m (690V)70A · 10m (690V)70A · 15m (690V)70A · 20m (690V)70A · 25m (690V)70A · 30m (690V)70A · 35m (690V)70A · 40m (690V)70A · 45m (690V)70A · 50m (690V)70A · 60m (690V)70A · 70m (690V)10A · 120m (690V)16A · 120m (690V)20A · 120m (690V)25A · 120m (690V)32A · 120m (690V)40A · 120m (690V)50A · 120m (690V)63A · 120m (690V)80A · 120m (690V)100A · 120m (690V)125A · 120m (690V)160A · 120m (690V)200A · 120m (690V)