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

250 Amp Cable Size at 50 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 50 m (164.0 ft).

Copper Cable (≤3% Drop)120 mm²Drop: 3.86V (0.56%)
Aluminum Cable (≤3% Drop)185 mm²Drop: 4.13V (0.6%)
Voltage at Load686.1 VLine Loss: 1671.9 W
Max Power & Breaker298.78 kW250A MCB/MCCB

IEC 60364 Cable Cross-Section Table (1.5 mm² – 400 mm²) for 250A at 50m

Cross-Section (mm²)Cu AmpacityAl Ampacity Cu Voltage DropLoad VoltageAl Voltage DropPower LossStatus
1.5 mm²16 A12 A308.88 V (44.77%)381.1 V509.51 V (73.84%)133750.0 WDrop High
2.5 mm²24 A18 A185.33 V (26.86%)504.7 V305.71 V (44.31%)80250.0 WDrop High
4 mm²32 A25 A115.83 V (16.79%)574.2 V191.07 V (27.69%)50156.2 WDrop High
6 mm²41 A32 A77.22 V (11.19%)612.8 V127.38 V (18.46%)33437.5 WDrop High
10 mm²57 A44 A46.33 V (6.71%)643.7 V76.43 V (11.08%)20062.5 WDrop High
16 mm²76 A59 A28.96 V (4.2%)661.0 V47.77 V (6.92%)12539.1 WDrop High
25 mm²101 A78 A18.53 V (2.69%)671.5 V30.57 V (4.43%)8025.0 WDrop High
35 mm²125 A97 A13.24 V (1.92%)676.8 V21.84 V (3.16%)5732.1 WDrop High
50 mm²151 A118 A9.27 V (1.34%)680.7 V15.29 V (2.22%)4012.5 WDrop High
70 mm²192 A150 A6.62 V (0.96%)683.4 V10.92 V (1.58%)2866.1 WDrop High
95 mm²232 A181 A4.88 V (0.71%)685.1 V8.04 V (1.17%)2111.8 WDrop High
120 mm²269 A210 A3.86 V (0.56%)686.1 V6.37 V (0.92%)1671.9 W✓ OK (≤3%)
150 mm²309 A241 A3.09 V (0.45%)686.9 V5.1 V (0.74%)1337.5 W✓ OK (≤3%)
185 mm²353 A275 A2.5 V (0.36%)687.5 V4.13 V (0.6%)1084.5 W✓ OK (≤3%)
240 mm²415 A324 A1.93 V (0.28%)688.1 V3.18 V (0.46%)835.9 W✓ OK (≤3%)
300 mm²477 A372 A1.54 V (0.22%)688.5 V2.55 V (0.37%)668.7 W✓ OK (≤3%)
400 mm²570 A445 A1.16 V (0.17%)688.8 V1.91 V (0.28%)501.6 W✓ OK (≤3%)

FAQ — 250 Amp Cable Size at 50 Meters (690V Three-Phase (Wind / Heavy Industrial))

What mm² cable size is required for 250A at 50 meters (690V)?

According to IEC 60364-5-52 ampacity and the 3% maximum voltage drop standard, you need 120 mm² copper cable for 250A over 50m at 690V (voltage drop: 3.86V or 0.56%).

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.