40 Amp Cable Size at 250 Meters (48V DC (LiFePO4 Battery Bank / Telecom))
IEC 60364-5-52 metric conductor sizing (mm²), voltage drop, and power loss calculation for 40 A over 250 m (820.2 ft).
Copper Cable (≤3% Drop)300 mm²Drop: 1.43V (2.97%)
Aluminum Cable (≤3% Drop)400 mm²Drop: 1.76V (3.68%)
Voltage at Load46.6 VLine Loss: 57.1 W
Max Power & Breaker1.92 kW40A MCB/MCCB
IEC 60364 Cable Cross-Section Table (1.5 mm² – 400 mm²) for 40A at 250m
| 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 | 285.33 V (594.44%) | 0.0 V | 470.67 V (980.56%) | 11413.3 W | Drop High |
| 2.5 mm² | 24 A | 18 A | 171.2 V (356.67%) | 0.0 V | 282.4 V (588.33%) | 6848.0 W | Drop High |
| 4 mm² | 32 A | 25 A | 107.0 V (222.92%) | 0.0 V | 176.5 V (367.71%) | 4280.0 W | Drop High |
| 6 mm² | 41 A | 32 A | 71.33 V (148.61%) | 0.0 V | 117.67 V (245.14%) | 2853.3 W | Drop High |
| 10 mm² | 57 A | 44 A | 42.8 V (89.17%) | 5.2 V | 70.6 V (147.08%) | 1712.0 W | Drop High |
| 16 mm² | 76 A | 59 A | 26.75 V (55.73%) | 21.2 V | 44.12 V (91.93%) | 1070.0 W | Drop High |
| 25 mm² | 101 A | 78 A | 17.12 V (35.67%) | 30.9 V | 28.24 V (58.83%) | 684.8 W | Drop High |
| 35 mm² | 125 A | 97 A | 12.23 V (25.48%) | 35.8 V | 20.17 V (42.02%) | 489.1 W | Drop High |
| 50 mm² | 151 A | 118 A | 8.56 V (17.83%) | 39.4 V | 14.12 V (29.42%) | 342.4 W | Drop High |
| 70 mm² | 192 A | 150 A | 6.11 V (12.74%) | 41.9 V | 10.09 V (21.01%) | 244.6 W | Drop High |
| 95 mm² | 232 A | 181 A | 4.51 V (9.39%) | 43.5 V | 7.43 V (15.48%) | 180.2 W | Drop High |
| 120 mm² | 269 A | 210 A | 3.57 V (7.43%) | 44.4 V | 5.88 V (12.26%) | 142.7 W | Drop High |
| 150 mm² | 309 A | 241 A | 2.85 V (5.94%) | 45.1 V | 4.71 V (9.81%) | 114.1 W | Drop High |
| 185 mm² | 353 A | 275 A | 2.31 V (4.82%) | 45.7 V | 3.82 V (7.95%) | 92.5 W | ~ ≤5% |
| 240 mm² | 415 A | 324 A | 1.78 V (3.72%) | 46.2 V | 2.94 V (6.13%) | 71.3 W | ~ ≤5% |
| 300 mm² | 477 A | 372 A | 1.43 V (2.97%) | 46.6 V | 2.35 V (4.9%) | 57.1 W | ✓ OK (≤3%) |
| 400 mm² | 570 A | 445 A | 1.07 V (2.23%) | 46.9 V | 1.76 V (3.68%) | 42.8 W | ✓ OK (≤3%) |
FAQ — 40 Amp Cable Size at 250 Meters (48V DC (LiFePO4 Battery Bank / Telecom))
What mm² cable size is required for 40A at 250 meters (48V)?
According to IEC 60364-5-52 ampacity and the 3% maximum voltage drop standard, you need 300 mm² copper cable for 40A over 250m at 48V (voltage drop: 1.43V or 2.97%).
What is the power capacity of 40A at 48V?
At unity power factor, 40A at 48V supports 1.92 kW with a standard 40A circuit breaker.
Related Lengths & Currents (48V)
40A · 5m (48V)40A · 10m (48V)40A · 15m (48V)40A · 20m (48V)40A · 25m (48V)40A · 30m (48V)40A · 35m (48V)40A · 40m (48V)40A · 45m (48V)40A · 50m (48V)40A · 60m (48V)40A · 70m (48V)10A · 250m (48V)16A · 250m (48V)20A · 250m (48V)25A · 250m (48V)32A · 250m (48V)50A · 250m (48V)63A · 250m (48V)80A · 250m (48V)100A · 250m (48V)125A · 250m (48V)160A · 250m (48V)200A · 250m (48V)