70 Amp Cable Size at 120 Meters (24V DC (Off-Grid Solar / Industrial Control))
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)2× 400 mm²Drop: 0.45V (1.88%)
Aluminum Cable (≤3% Drop)400 mm²Drop: 1.48V (6.18%)
Voltage at Load23.6 VLine Loss: 31.4 W
Max Power & Breaker1.68 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 | 239.68 V (998.67%) | 0.0 V | 395.36 V (1647.33%) | 16777.6 W | Drop High |
| 2.5 mm² | 24 A | 18 A | 143.81 V (599.2%) | 0.0 V | 237.22 V (988.4%) | 10066.6 W | Drop High |
| 4 mm² | 32 A | 25 A | 89.88 V (374.5%) | 0.0 V | 148.26 V (617.75%) | 6291.6 W | Drop High |
| 6 mm² | 41 A | 32 A | 59.92 V (249.67%) | 0.0 V | 98.84 V (411.83%) | 4194.4 W | Drop High |
| 10 mm² | 57 A | 44 A | 35.95 V (149.8%) | 0.0 V | 59.3 V (247.1%) | 2516.6 W | Drop High |
| 16 mm² | 76 A | 59 A | 22.47 V (93.62%) | 1.5 V | 37.06 V (154.44%) | 1572.9 W | Drop High |
| 25 mm² | 101 A | 78 A | 14.38 V (59.92%) | 9.6 V | 23.72 V (98.84%) | 1006.7 W | Drop High |
| 35 mm² | 125 A | 97 A | 10.27 V (42.8%) | 13.7 V | 16.94 V (70.6%) | 719.0 W | Drop High |
| 50 mm² | 151 A | 118 A | 7.19 V (29.96%) | 16.8 V | 11.86 V (49.42%) | 503.3 W | Drop High |
| 70 mm² | 192 A | 150 A | 5.14 V (21.4%) | 18.9 V | 8.47 V (35.3%) | 359.5 W | Drop High |
| 95 mm² | 232 A | 181 A | 3.78 V (15.77%) | 20.2 V | 6.24 V (26.01%) | 264.9 W | Drop High |
| 120 mm² | 269 A | 210 A | 3.0 V (12.48%) | 21.0 V | 4.94 V (20.59%) | 209.7 W | Drop High |
| 150 mm² | 309 A | 241 A | 2.4 V (9.99%) | 21.6 V | 3.95 V (16.47%) | 167.8 W | Drop High |
| 185 mm² | 353 A | 275 A | 1.94 V (8.1%) | 22.1 V | 3.21 V (13.36%) | 136.0 W | Drop High |
| 240 mm² | 415 A | 324 A | 1.5 V (6.24%) | 22.5 V | 2.47 V (10.3%) | 104.9 W | Drop High |
| 300 mm² | 477 A | 372 A | 1.2 V (4.99%) | 22.8 V | 1.98 V (8.24%) | 83.9 W | ~ ≤5% |
| 400 mm² | 570 A | 445 A | 0.9 V (3.75%) | 23.1 V | 1.48 V (6.18%) | 62.9 W | ~ ≤5% |
FAQ — 70 Amp Cable Size at 120 Meters (24V DC (Off-Grid Solar / Industrial Control))
What mm² cable size is required for 70A at 120 meters (24V)?
According to IEC 60364-5-52 ampacity and the 3% maximum voltage drop standard, you need 2× 400 mm² copper cable for 70A over 120m at 24V (voltage drop: 0.45V or 1.88%).
What is the power capacity of 70A at 24V?
At unity power factor, 70A at 24V supports 1.68 kW with a standard 70A circuit breaker.
Related Lengths & Currents (24V)
70A · 5m (24V)70A · 10m (24V)70A · 15m (24V)70A · 20m (24V)70A · 25m (24V)70A · 30m (24V)70A · 35m (24V)70A · 40m (24V)70A · 45m (24V)70A · 50m (24V)70A · 60m (24V)70A · 70m (24V)10A · 120m (24V)16A · 120m (24V)20A · 120m (24V)25A · 120m (24V)32A · 120m (24V)40A · 120m (24V)50A · 120m (24V)63A · 120m (24V)80A · 120m (24V)100A · 120m (24V)125A · 120m (24V)160A · 120m (24V)200A · 120m (24V)