40 Amp Cable Size at 120 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 120 m (393.7 ft).
Copper Cable (≤3% Drop)150 mm²Drop: 1.37V (2.85%)
Aluminum Cable (≤3% Drop)240 mm²Drop: 1.41V (2.94%)
Voltage at Load46.6 VLine Loss: 54.8 W
Max Power & Breaker1.92 kW40A MCB/MCCB
IEC 60364 Cable Cross-Section Table (1.5 mm² – 400 mm²) for 40A 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 | 136.96 V (285.33%) | 0.0 V | 225.92 V (470.67%) | 5478.4 W | Drop High |
| 2.5 mm² | 24 A | 18 A | 82.18 V (171.2%) | 0.0 V | 135.55 V (282.4%) | 3287.0 W | Drop High |
| 4 mm² | 32 A | 25 A | 51.36 V (107.0%) | 0.0 V | 84.72 V (176.5%) | 2054.4 W | Drop High |
| 6 mm² | 41 A | 32 A | 34.24 V (71.33%) | 13.8 V | 56.48 V (117.67%) | 1369.6 W | Drop High |
| 10 mm² | 57 A | 44 A | 20.54 V (42.8%) | 27.5 V | 33.89 V (70.6%) | 821.8 W | Drop High |
| 16 mm² | 76 A | 59 A | 12.84 V (26.75%) | 35.2 V | 21.18 V (44.12%) | 513.6 W | Drop High |
| 25 mm² | 101 A | 78 A | 8.22 V (17.12%) | 39.8 V | 13.56 V (28.24%) | 328.7 W | Drop High |
| 35 mm² | 125 A | 97 A | 5.87 V (12.23%) | 42.1 V | 9.68 V (20.17%) | 234.8 W | Drop High |
| 50 mm² | 151 A | 118 A | 4.11 V (8.56%) | 43.9 V | 6.78 V (14.12%) | 164.4 W | Drop High |
| 70 mm² | 192 A | 150 A | 2.93 V (6.11%) | 45.1 V | 4.84 V (10.09%) | 117.4 W | Drop High |
| 95 mm² | 232 A | 181 A | 2.16 V (4.51%) | 45.8 V | 3.57 V (7.43%) | 86.5 W | ~ ≤5% |
| 120 mm² | 269 A | 210 A | 1.71 V (3.57%) | 46.3 V | 2.82 V (5.88%) | 68.5 W | ~ ≤5% |
| 150 mm² | 309 A | 241 A | 1.37 V (2.85%) | 46.6 V | 2.26 V (4.71%) | 54.8 W | ✓ OK (≤3%) |
| 185 mm² | 353 A | 275 A | 1.11 V (2.31%) | 46.9 V | 1.83 V (3.82%) | 44.4 W | ✓ OK (≤3%) |
| 240 mm² | 415 A | 324 A | 0.86 V (1.78%) | 47.1 V | 1.41 V (2.94%) | 34.2 W | ✓ OK (≤3%) |
| 300 mm² | 477 A | 372 A | 0.68 V (1.43%) | 47.3 V | 1.13 V (2.35%) | 27.4 W | ✓ OK (≤3%) |
| 400 mm² | 570 A | 445 A | 0.51 V (1.07%) | 47.5 V | 0.85 V (1.76%) | 20.5 W | ✓ OK (≤3%) |
FAQ — 40 Amp Cable Size at 120 Meters (48V DC (LiFePO4 Battery Bank / Telecom))
What mm² cable size is required for 40A at 120 meters (48V)?
According to IEC 60364-5-52 ampacity and the 3% maximum voltage drop standard, you need 150 mm² copper cable for 40A over 120m at 48V (voltage drop: 1.37V or 2.85%).
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 · 120m (48V)16A · 120m (48V)20A · 120m (48V)25A · 120m (48V)32A · 120m (48V)50A · 120m (48V)63A · 120m (48V)80A · 120m (48V)100A · 120m (48V)125A · 120m (48V)160A · 120m (48V)200A · 120m (48V)