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

250 Amp Cable Size at 350 Meters (690V Three-Phase (Wind / Heavy Industrial))

IEC 60364-5-52 metric conductor sizing (mm²), voltage drop, and power loss calculation for 250 A over 350 m (1148.3 ft).

Copper Cable (≤3% Drop)185 mm²Drop: 17.53V (2.54%)
Aluminum Cable (≤3% Drop)300 mm²Drop: 17.83V (2.58%)
Voltage at Load672.5 VLine Loss: 7591.2 W
Max Power & Breaker298.78 kW250A MCB/MCCB

IEC 60364 Cable Cross-Section Table (1.5 mm² – 400 mm²) for 250A at 350m

Cross-Section (mm²)Cu AmpacityAl Ampacity Cu Voltage DropLoad VoltageAl Voltage DropPower LossStatus
1.5 mm²16 A12 A2162.18 V (313.36%)0.0 V3566.58 V (516.9%)936250.0 WDrop High
2.5 mm²24 A18 A1297.31 V (188.02%)0.0 V2139.95 V (310.14%)561750.0 WDrop High
4 mm²32 A25 A810.82 V (117.51%)0.0 V1337.47 V (193.84%)351093.7 WDrop High
6 mm²41 A32 A540.54 V (78.34%)149.5 V891.65 V (129.22%)234062.5 WDrop High
10 mm²57 A44 A324.33 V (47.0%)365.7 V534.99 V (77.53%)140437.5 WDrop High
16 mm²76 A59 A202.7 V (29.38%)487.3 V334.37 V (48.46%)87773.4 WDrop High
25 mm²101 A78 A129.73 V (18.8%)560.3 V213.99 V (31.01%)56175.0 WDrop High
35 mm²125 A97 A92.66 V (13.43%)597.3 V152.85 V (22.15%)40125.0 WDrop High
50 mm²151 A118 A64.87 V (9.4%)625.1 V107.0 V (15.51%)28087.5 WDrop High
70 mm²192 A150 A46.33 V (6.71%)643.7 V76.43 V (11.08%)20062.5 WDrop High
95 mm²232 A181 A34.14 V (4.95%)655.9 V56.31 V (8.16%)14782.9 WDrop High
120 mm²269 A210 A27.03 V (3.92%)663.0 V44.58 V (6.46%)11703.1 W~ ≤5%
150 mm²309 A241 A21.62 V (3.13%)668.4 V35.67 V (5.17%)9362.5 W~ ≤5%
185 mm²353 A275 A17.53 V (2.54%)672.5 V28.92 V (4.19%)7591.2 W✓ OK (≤3%)
240 mm²415 A324 A13.51 V (1.96%)676.5 V22.29 V (3.23%)5851.6 W✓ OK (≤3%)
300 mm²477 A372 A10.81 V (1.57%)679.2 V17.83 V (2.58%)4681.2 W✓ OK (≤3%)
400 mm²570 A445 A8.11 V (1.18%)681.9 V13.37 V (1.94%)3510.9 W✓ OK (≤3%)

FAQ — 250 Amp Cable Size at 350 Meters (690V Three-Phase (Wind / Heavy Industrial))

What mm² cable size is required for 250A at 350 meters (690V)?

According to IEC 60364-5-52 ampacity and the 3% maximum voltage drop standard, you need 185 mm² copper cable for 250A over 350m at 690V (voltage drop: 17.53V or 2.54%).

What is the power capacity of 250A at 690V?

At unity power factor, 250A at 690V supports 298.78 kW with a standard 250A circuit breaker.