40 Amp Cable Size at 30 Meters (24V DC (Off-Grid Solar / Industrial Control))
IEC 60364-5-52 metric conductor sizing (mm²), voltage drop, and power loss calculation for 40 A over 30 m (98.4 ft).
Copper Cable (≤3% Drop)95 mm²Drop: 0.54V (2.25%)
Aluminum Cable (≤3% Drop)120 mm²Drop: 0.71V (2.94%)
Voltage at Load23.5 VLine Loss: 21.6 W
Max Power & Breaker0.96 kW40A MCB/MCCB
IEC 60364 Cable Cross-Section Table (1.5 mm² – 400 mm²) for 40A at 30m
| 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 | 34.24 V (142.67%) | 0.0 V | 56.48 V (235.33%) | 1369.6 W | Drop High |
| 2.5 mm² | 24 A | 18 A | 20.54 V (85.6%) | 3.5 V | 33.89 V (141.2%) | 821.8 W | Drop High |
| 4 mm² | 32 A | 25 A | 12.84 V (53.5%) | 11.2 V | 21.18 V (88.25%) | 513.6 W | Drop High |
| 6 mm² | 41 A | 32 A | 8.56 V (35.67%) | 15.4 V | 14.12 V (58.83%) | 342.4 W | Drop High |
| 10 mm² | 57 A | 44 A | 5.14 V (21.4%) | 18.9 V | 8.47 V (35.3%) | 205.4 W | Drop High |
| 16 mm² | 76 A | 59 A | 3.21 V (13.38%) | 20.8 V | 5.29 V (22.06%) | 128.4 W | Drop High |
| 25 mm² | 101 A | 78 A | 2.05 V (8.56%) | 21.9 V | 3.39 V (14.12%) | 82.2 W | Drop High |
| 35 mm² | 125 A | 97 A | 1.47 V (6.11%) | 22.5 V | 2.42 V (10.09%) | 58.7 W | Drop High |
| 50 mm² | 151 A | 118 A | 1.03 V (4.28%) | 23.0 V | 1.69 V (7.06%) | 41.1 W | ~ ≤5% |
| 70 mm² | 192 A | 150 A | 0.73 V (3.06%) | 23.3 V | 1.21 V (5.04%) | 29.3 W | ~ ≤5% |
| 95 mm² | 232 A | 181 A | 0.54 V (2.25%) | 23.5 V | 0.89 V (3.72%) | 21.6 W | ✓ OK (≤3%) |
| 120 mm² | 269 A | 210 A | 0.43 V (1.78%) | 23.6 V | 0.71 V (2.94%) | 17.1 W | ✓ OK (≤3%) |
| 150 mm² | 309 A | 241 A | 0.34 V (1.43%) | 23.7 V | 0.56 V (2.35%) | 13.7 W | ✓ OK (≤3%) |
| 185 mm² | 353 A | 275 A | 0.28 V (1.16%) | 23.7 V | 0.46 V (1.91%) | 11.1 W | ✓ OK (≤3%) |
| 240 mm² | 415 A | 324 A | 0.21 V (0.89%) | 23.8 V | 0.35 V (1.47%) | 8.6 W | ✓ OK (≤3%) |
| 300 mm² | 477 A | 372 A | 0.17 V (0.71%) | 23.8 V | 0.28 V (1.18%) | 6.8 W | ✓ OK (≤3%) |
| 400 mm² | 570 A | 445 A | 0.13 V (0.54%) | 23.9 V | 0.21 V (0.88%) | 5.1 W | ✓ OK (≤3%) |
FAQ — 40 Amp Cable Size at 30 Meters (24V DC (Off-Grid Solar / Industrial Control))
What mm² cable size is required for 40A at 30 meters (24V)?
According to IEC 60364-5-52 ampacity and the 3% maximum voltage drop standard, you need 95 mm² copper cable for 40A over 30m at 24V (voltage drop: 0.54V or 2.25%).
What is the power capacity of 40A at 24V?
At unity power factor, 40A at 24V supports 0.96 kW with a standard 40A circuit breaker.
Related Lengths & Currents (24V)
40A · 5m (24V)40A · 10m (24V)40A · 15m (24V)40A · 20m (24V)40A · 25m (24V)40A · 35m (24V)40A · 40m (24V)40A · 45m (24V)40A · 50m (24V)40A · 60m (24V)40A · 70m (24V)10A · 30m (24V)16A · 30m (24V)20A · 30m (24V)25A · 30m (24V)32A · 30m (24V)50A · 30m (24V)63A · 30m (24V)80A · 30m (24V)100A · 30m (24V)125A · 30m (24V)160A · 30m (24V)200A · 30m (24V)