25 Amp Cable Size at 70 Meters (690V Three-Phase (Wind / Heavy Industrial))
IEC 60364-5-52 metric conductor sizing (mm²), voltage drop, and power loss calculation for 25 A over 70 m (229.7 ft).
Copper Cable (≤3% Drop)4 mm²Drop: 16.22V (2.35%)
Aluminum Cable (≤3% Drop)6 mm²Drop: 17.83V (2.58%)
Voltage at Load673.8 VLine Loss: 702.2 W
Max Power & Breaker29.88 kW25A MCB/MCCB
IEC 60364 Cable Cross-Section Table (1.5 mm² – 400 mm²) for 25A 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 | 43.24 V (6.27%) | 646.8 V | 71.33 V (10.34%) | 1872.5 W | Drop High |
| 2.5 mm² | 24 A | 18 A | 25.95 V (3.76%) | 664.1 V | 42.8 V (6.2%) | 1123.5 W | Drop High |
| 4 mm² | 32 A | 25 A | 16.22 V (2.35%) | 673.8 V | 26.75 V (3.88%) | 702.2 W | ✓ OK (≤3%) |
| 6 mm² | 41 A | 32 A | 10.81 V (1.57%) | 679.2 V | 17.83 V (2.58%) | 468.1 W | ✓ OK (≤3%) |
| 10 mm² | 57 A | 44 A | 6.49 V (0.94%) | 683.5 V | 10.7 V (1.55%) | 280.9 W | ✓ OK (≤3%) |
| 16 mm² | 76 A | 59 A | 4.05 V (0.59%) | 685.9 V | 6.69 V (0.97%) | 175.5 W | ✓ OK (≤3%) |
| 25 mm² | 101 A | 78 A | 2.59 V (0.38%) | 687.4 V | 4.28 V (0.62%) | 112.4 W | ✓ OK (≤3%) |
| 35 mm² | 125 A | 97 A | 1.85 V (0.27%) | 688.1 V | 3.06 V (0.44%) | 80.2 W | ✓ OK (≤3%) |
| 50 mm² | 151 A | 118 A | 1.3 V (0.19%) | 688.7 V | 2.14 V (0.31%) | 56.2 W | ✓ OK (≤3%) |
| 70 mm² | 192 A | 150 A | 0.93 V (0.13%) | 689.1 V | 1.53 V (0.22%) | 40.1 W | ✓ OK (≤3%) |
| 95 mm² | 232 A | 181 A | 0.68 V (0.1%) | 689.3 V | 1.13 V (0.16%) | 29.6 W | ✓ OK (≤3%) |
| 120 mm² | 269 A | 210 A | 0.54 V (0.08%) | 689.5 V | 0.89 V (0.13%) | 23.4 W | ✓ OK (≤3%) |
| 150 mm² | 309 A | 241 A | 0.43 V (0.06%) | 689.6 V | 0.71 V (0.1%) | 18.7 W | ✓ OK (≤3%) |
| 185 mm² | 353 A | 275 A | 0.35 V (0.05%) | 689.6 V | 0.58 V (0.08%) | 15.2 W | ✓ OK (≤3%) |
| 240 mm² | 415 A | 324 A | 0.27 V (0.04%) | 689.7 V | 0.45 V (0.06%) | 11.7 W | ✓ OK (≤3%) |
| 300 mm² | 477 A | 372 A | 0.22 V (0.03%) | 689.8 V | 0.36 V (0.05%) | 9.4 W | ✓ OK (≤3%) |
| 400 mm² | 570 A | 445 A | 0.16 V (0.02%) | 689.8 V | 0.27 V (0.04%) | 7.0 W | ✓ OK (≤3%) |
FAQ — 25 Amp Cable Size at 70 Meters (690V Three-Phase (Wind / Heavy Industrial))
What mm² cable size is required for 25A at 70 meters (690V)?
According to IEC 60364-5-52 ampacity and the 3% maximum voltage drop standard, you need 4 mm² copper cable for 25A over 70m at 690V (voltage drop: 16.22V or 2.35%).
What is the power capacity of 25A at 690V?
At unity power factor, 25A at 690V supports 29.88 kW with a standard 25A circuit breaker.
Related Lengths & Currents (690V)
25A · 5m (690V)25A · 10m (690V)25A · 15m (690V)25A · 20m (690V)25A · 25m (690V)25A · 30m (690V)25A · 35m (690V)25A · 40m (690V)25A · 45m (690V)25A · 50m (690V)25A · 60m (690V)10A · 70m (690V)16A · 70m (690V)20A · 70m (690V)32A · 70m (690V)40A · 70m (690V)50A · 70m (690V)63A · 70m (690V)80A · 70m (690V)100A · 70m (690V)125A · 70m (690V)160A · 70m (690V)200A · 70m (690V)