425 Amp Cable Size at 20 Meters (690V Three-Phase (Wind / Heavy Industrial))
IEC 60364-5-52 metric conductor sizing (mm²), voltage drop, and power loss calculation for 425 A over 20 m (65.6 ft).
Copper Cable (≤3% Drop)300 mm²Drop: 1.05V (0.15%)
Aluminum Cable (≤3% Drop)400 mm²Drop: 1.3V (0.19%)
Voltage at Load688.9 VLine Loss: 773.1 W
Max Power & Breaker507.92 kW450A MCB/MCCB
IEC 60364 Cable Cross-Section Table (1.5 mm² – 400 mm²) for 425A at 20m
| 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 | 210.04 V (30.44%) | 480.0 V | 346.47 V (50.21%) | 154615.0 W | Drop High |
| 2.5 mm² | 24 A | 18 A | 126.02 V (18.26%) | 564.0 V | 207.88 V (30.13%) | 92769.0 W | Drop High |
| 4 mm² | 32 A | 25 A | 78.77 V (11.42%) | 611.2 V | 129.93 V (18.83%) | 57980.6 W | Drop High |
| 6 mm² | 41 A | 32 A | 52.51 V (7.61%) | 637.5 V | 86.62 V (12.55%) | 38653.8 W | Drop High |
| 10 mm² | 57 A | 44 A | 31.51 V (4.57%) | 658.5 V | 51.97 V (7.53%) | 23192.2 W | Drop High |
| 16 mm² | 76 A | 59 A | 19.69 V (2.85%) | 670.3 V | 32.48 V (4.71%) | 14495.2 W | Drop High |
| 25 mm² | 101 A | 78 A | 12.6 V (1.83%) | 677.4 V | 20.79 V (3.01%) | 9276.9 W | Drop High |
| 35 mm² | 125 A | 97 A | 9.0 V (1.3%) | 681.0 V | 14.85 V (2.15%) | 6626.4 W | Drop High |
| 50 mm² | 151 A | 118 A | 6.3 V (0.91%) | 683.7 V | 10.39 V (1.51%) | 4638.4 W | Drop High |
| 70 mm² | 192 A | 150 A | 4.5 V (0.65%) | 685.5 V | 7.42 V (1.08%) | 3313.2 W | Drop High |
| 95 mm² | 232 A | 181 A | 3.32 V (0.48%) | 686.7 V | 5.47 V (0.79%) | 2441.3 W | Drop High |
| 120 mm² | 269 A | 210 A | 2.63 V (0.38%) | 687.4 V | 4.33 V (0.63%) | 1932.7 W | Drop High |
| 150 mm² | 309 A | 241 A | 2.1 V (0.3%) | 687.9 V | 3.46 V (0.5%) | 1546.1 W | Drop High |
| 185 mm² | 353 A | 275 A | 1.7 V (0.25%) | 688.3 V | 2.81 V (0.41%) | 1253.6 W | Drop High |
| 240 mm² | 415 A | 324 A | 1.31 V (0.19%) | 688.7 V | 2.17 V (0.31%) | 966.3 W | Drop High |
| 300 mm² | 477 A | 372 A | 1.05 V (0.15%) | 688.9 V | 1.73 V (0.25%) | 773.1 W | ✓ OK (≤3%) |
| 400 mm² | 570 A | 445 A | 0.79 V (0.11%) | 689.2 V | 1.3 V (0.19%) | 579.8 W | ✓ OK (≤3%) |
FAQ — 425 Amp Cable Size at 20 Meters (690V Three-Phase (Wind / Heavy Industrial))
What mm² cable size is required for 425A at 20 meters (690V)?
According to IEC 60364-5-52 ampacity and the 3% maximum voltage drop standard, you need 300 mm² copper cable for 425A over 20m at 690V (voltage drop: 1.05V or 0.15%).
What is the power capacity of 425A at 690V?
At unity power factor, 425A at 690V supports 507.92 kW with a standard 450A circuit breaker.
Related Lengths & Currents (690V)
425A · 5m (690V)425A · 10m (690V)425A · 15m (690V)425A · 25m (690V)425A · 30m (690V)425A · 35m (690V)425A · 40m (690V)425A · 45m (690V)425A · 50m (690V)425A · 60m (690V)425A · 70m (690V)10A · 20m (690V)16A · 20m (690V)20A · 20m (690V)25A · 20m (690V)32A · 20m (690V)40A · 20m (690V)50A · 20m (690V)63A · 20m (690V)80A · 20m (690V)100A · 20m (690V)125A · 20m (690V)160A · 20m (690V)200A · 20m (690V)