300 Amp Cable Size at 70 Meters (24V DC (Off-Grid Solar / Industrial Control))
IEC 60364-5-52 metric conductor sizing (mm²), voltage drop, and power loss calculation for 300 A over 70 m (229.7 ft).
Copper Cable (≤3% Drop)4× 400 mm²Drop: 0.56V (2.34%)
Aluminum Cable (≤3% Drop)400 mm²Drop: 3.71V (15.44%)
Voltage at Load23.4 VLine Loss: 168.5 W
Max Power & Breaker7.2 kW300A MCB/MCCB
IEC 60364 Cable Cross-Section Table (1.5 mm² – 400 mm²) for 300A 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 | 599.2 V (2496.67%) | 0.0 V | 988.4 V (4118.33%) | 179760.0 W | Drop High |
| 2.5 mm² | 24 A | 18 A | 359.52 V (1498.0%) | 0.0 V | 593.04 V (2471.0%) | 107856.0 W | Drop High |
| 4 mm² | 32 A | 25 A | 224.7 V (936.25%) | 0.0 V | 370.65 V (1544.38%) | 67410.0 W | Drop High |
| 6 mm² | 41 A | 32 A | 149.8 V (624.17%) | 0.0 V | 247.1 V (1029.58%) | 44940.0 W | Drop High |
| 10 mm² | 57 A | 44 A | 89.88 V (374.5%) | 0.0 V | 148.26 V (617.75%) | 26964.0 W | Drop High |
| 16 mm² | 76 A | 59 A | 56.17 V (234.06%) | 0.0 V | 92.66 V (386.09%) | 16852.5 W | Drop High |
| 25 mm² | 101 A | 78 A | 35.95 V (149.8%) | 0.0 V | 59.3 V (247.1%) | 10785.6 W | Drop High |
| 35 mm² | 125 A | 97 A | 25.68 V (107.0%) | 0.0 V | 42.36 V (176.5%) | 7704.0 W | Drop High |
| 50 mm² | 151 A | 118 A | 17.98 V (74.9%) | 6.0 V | 29.65 V (123.55%) | 5392.8 W | Drop High |
| 70 mm² | 192 A | 150 A | 12.84 V (53.5%) | 11.2 V | 21.18 V (88.25%) | 3852.0 W | Drop High |
| 95 mm² | 232 A | 181 A | 9.46 V (39.42%) | 14.5 V | 15.61 V (65.03%) | 2838.3 W | Drop High |
| 120 mm² | 269 A | 210 A | 7.49 V (31.21%) | 16.5 V | 12.36 V (51.48%) | 2247.0 W | Drop High |
| 150 mm² | 309 A | 241 A | 5.99 V (24.97%) | 18.0 V | 9.88 V (41.18%) | 1797.6 W | Drop High |
| 185 mm² | 353 A | 275 A | 4.86 V (20.24%) | 19.1 V | 8.01 V (33.39%) | 1457.5 W | Drop High |
| 240 mm² | 415 A | 324 A | 3.75 V (15.6%) | 20.3 V | 6.18 V (25.74%) | 1123.5 W | Drop High |
| 300 mm² | 477 A | 372 A | 3.0 V (12.48%) | 21.0 V | 4.94 V (20.59%) | 898.8 W | Drop High |
| 400 mm² | 570 A | 445 A | 2.25 V (9.36%) | 21.8 V | 3.71 V (15.44%) | 674.1 W | Drop High |
FAQ — 300 Amp Cable Size at 70 Meters (24V DC (Off-Grid Solar / Industrial Control))
What mm² cable size is required for 300A at 70 meters (24V)?
According to IEC 60364-5-52 ampacity and the 3% maximum voltage drop standard, you need 4× 400 mm² copper cable for 300A over 70m at 24V (voltage drop: 0.56V or 2.34%).
What is the power capacity of 300A at 24V?
At unity power factor, 300A at 24V supports 7.2 kW with a standard 300A circuit breaker.
Related Lengths & Currents (24V)
300A · 5m (24V)300A · 10m (24V)300A · 15m (24V)300A · 20m (24V)300A · 25m (24V)300A · 30m (24V)300A · 35m (24V)300A · 40m (24V)300A · 45m (24V)300A · 50m (24V)300A · 60m (24V)10A · 70m (24V)16A · 70m (24V)20A · 70m (24V)25A · 70m (24V)32A · 70m (24V)40A · 70m (24V)50A · 70m (24V)63A · 70m (24V)80A · 70m (24V)100A · 70m (24V)125A · 70m (24V)160A · 70m (24V)200A · 70m (24V)