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⚡ IEC 60364-5-52 · DIN VDE · NEK 400 · SS 436 40 00

425 Amp Cable Size at 120 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 120 m (393.7 ft).

Copper Cable (≤3% Drop)300 mm²Drop: 6.3V (0.91%)
Aluminum Cable (≤3% Drop)400 mm²Drop: 7.8V (1.13%)
Voltage at Load683.7 VLine Loss: 4638.4 W
Max Power & Breaker507.92 kW450A MCB/MCCB

IEC 60364 Cable Cross-Section Table (1.5 mm² – 400 mm²) for 425A at 120m

Cross-Section (mm²)Cu AmpacityAl Ampacity Cu Voltage DropLoad VoltageAl Voltage DropPower LossStatus
1.5 mm²16 A12 A1260.24 V (182.64%)0.0 V2078.81 V (301.28%)927690.0 WDrop High
2.5 mm²24 A18 A756.14 V (109.59%)0.0 V1247.28 V (180.77%)556614.0 WDrop High
4 mm²32 A25 A472.59 V (68.49%)217.4 V779.55 V (112.98%)347883.8 WDrop High
6 mm²41 A32 A315.06 V (45.66%)374.9 V519.7 V (75.32%)231922.5 WDrop High
10 mm²57 A44 A189.04 V (27.4%)501.0 V311.82 V (45.19%)139153.5 WDrop High
16 mm²76 A59 A118.15 V (17.12%)571.9 V194.89 V (28.24%)86970.9 WDrop High
25 mm²101 A78 A75.61 V (10.96%)614.4 V124.73 V (18.08%)55661.4 WDrop High
35 mm²125 A97 A54.01 V (7.83%)636.0 V89.09 V (12.91%)39758.1 WDrop High
50 mm²151 A118 A37.81 V (5.48%)652.2 V62.36 V (9.04%)27830.7 WDrop High
70 mm²192 A150 A27.01 V (3.91%)663.0 V44.55 V (6.46%)19879.1 WDrop High
95 mm²232 A181 A19.9 V (2.88%)670.1 V32.82 V (4.76%)14647.7 WDrop High
120 mm²269 A210 A15.75 V (2.28%)674.2 V25.99 V (3.77%)11596.1 WDrop High
150 mm²309 A241 A12.6 V (1.83%)677.4 V20.79 V (3.01%)9276.9 WDrop High
185 mm²353 A275 A10.22 V (1.48%)679.8 V16.86 V (2.44%)7521.8 WDrop High
240 mm²415 A324 A7.88 V (1.14%)682.1 V12.99 V (1.88%)5798.1 WDrop High
300 mm²477 A372 A6.3 V (0.91%)683.7 V10.39 V (1.51%)4638.4 W✓ OK (≤3%)
400 mm²570 A445 A4.73 V (0.68%)685.3 V7.8 V (1.13%)3478.8 W✓ OK (≤3%)

FAQ — 425 Amp Cable Size at 120 Meters (690V Three-Phase (Wind / Heavy Industrial))

What mm² cable size is required for 425A at 120 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 120m at 690V (voltage drop: 6.3V or 0.91%).

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.