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

250 Amp Cable Size at 250 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 250 m (820.2 ft).

Copper Cable (≤3% Drop)120 mm²Drop: 19.31V (2.8%)
Aluminum Cable (≤3% Drop)185 mm²Drop: 20.66V (2.99%)
Voltage at Load670.7 VLine Loss: 8359.4 W
Max Power & Breaker298.78 kW250A MCB/MCCB

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

Cross-Section (mm²)Cu AmpacityAl Ampacity Cu Voltage DropLoad VoltageAl Voltage DropPower LossStatus
1.5 mm²16 A12 A1544.41 V (223.83%)0.0 V2547.56 V (369.21%)668750.0 WDrop High
2.5 mm²24 A18 A926.65 V (134.3%)0.0 V1528.53 V (221.53%)401250.0 WDrop High
4 mm²32 A25 A579.15 V (83.94%)110.8 V955.33 V (138.45%)250781.2 WDrop High
6 mm²41 A32 A386.1 V (55.96%)303.9 V636.89 V (92.3%)167187.5 WDrop High
10 mm²57 A44 A231.66 V (33.57%)458.3 V382.13 V (55.38%)100312.5 WDrop High
16 mm²76 A59 A144.79 V (20.98%)545.2 V238.83 V (34.61%)62695.3 WDrop High
25 mm²101 A78 A92.66 V (13.43%)597.3 V152.85 V (22.15%)40125.0 WDrop High
35 mm²125 A97 A66.19 V (9.59%)623.8 V109.18 V (15.82%)28660.7 WDrop High
50 mm²151 A118 A46.33 V (6.71%)643.7 V76.43 V (11.08%)20062.5 WDrop High
70 mm²192 A150 A33.09 V (4.8%)656.9 V54.59 V (7.91%)14330.4 WDrop High
95 mm²232 A181 A24.39 V (3.53%)665.6 V40.22 V (5.83%)10559.2 WDrop High
120 mm²269 A210 A19.31 V (2.8%)670.7 V31.84 V (4.62%)8359.4 W✓ OK (≤3%)
150 mm²309 A241 A15.44 V (2.24%)674.6 V25.48 V (3.69%)6687.5 W✓ OK (≤3%)
185 mm²353 A275 A12.52 V (1.81%)677.5 V20.66 V (2.99%)5422.3 W✓ OK (≤3%)
240 mm²415 A324 A9.65 V (1.4%)680.3 V15.92 V (2.31%)4179.7 W✓ OK (≤3%)
300 mm²477 A372 A7.72 V (1.12%)682.3 V12.74 V (1.85%)3343.8 W✓ OK (≤3%)
400 mm²570 A445 A5.79 V (0.84%)684.2 V9.55 V (1.38%)2507.8 W✓ OK (≤3%)

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

What mm² cable size is required for 250A at 250 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 250m at 690V (voltage drop: 19.31V or 2.8%).

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.