⚡ Cu ρ (75°C): 0.0214 Ω·mm²/m 🔌 NEC / IEC Standards: NFPA 70 & IEC 60364 🇺🇸 US Grid Avg: $0.175/kWh 🇩🇪 DE Grid Avg: €0.345/kWh 🇸🇪 SE Elpris: 1.54 SEK/kWh 🇳🇴 NO Strøm: 1.17 NOK/kWh 🔩 Copper Ref: $9,650/t (2026-10-24)
⚡ IEC 60364-5-52 · DIN VDE · NEK 400 · SS 436 40 00

125 Amp Cable Size at 500 Meters (415V Three-Phase (UK / Australia Industrial))

IEC 60364-5-52 metric conductor sizing (mm²), voltage drop, and power loss calculation for 125 A over 500 m (1640.4 ft).

Copper Cable (≤3% Drop)240 mm²Drop: 9.65V (2.33%)
Aluminum Cable (≤3% Drop)400 mm²Drop: 9.55V (2.3%)
Voltage at Load405.3 VLine Loss: 2089.8 W
Max Power & Breaker89.85 kW125A MCB/MCCB

IEC 60364 Cable Cross-Section Table (1.5 mm² – 400 mm²) for 125A at 500m

Cross-Section (mm²)Cu AmpacityAl Ampacity Cu Voltage DropLoad VoltageAl Voltage DropPower LossStatus
1.5 mm²16 A12 A1544.41 V (372.15%)0.0 V2547.56 V (613.87%)334375.0 WDrop High
2.5 mm²24 A18 A926.65 V (223.29%)0.0 V1528.53 V (368.32%)200625.0 WDrop High
4 mm²32 A25 A579.15 V (139.56%)0.0 V955.33 V (230.2%)125390.6 WDrop High
6 mm²41 A32 A386.1 V (93.04%)28.9 V636.89 V (153.47%)83593.8 WDrop High
10 mm²57 A44 A231.66 V (55.82%)183.3 V382.13 V (92.08%)50156.2 WDrop High
16 mm²76 A59 A144.79 V (34.89%)270.2 V238.83 V (57.55%)31347.7 WDrop High
25 mm²101 A78 A92.66 V (22.33%)322.3 V152.85 V (36.83%)20062.5 WDrop High
35 mm²125 A97 A66.19 V (15.95%)348.8 V109.18 V (26.31%)14330.4 WDrop High
50 mm²151 A118 A46.33 V (11.16%)368.7 V76.43 V (18.42%)10031.2 WDrop High
70 mm²192 A150 A33.09 V (7.97%)381.9 V54.59 V (13.15%)7165.2 WDrop High
95 mm²232 A181 A24.39 V (5.88%)390.6 V40.22 V (9.69%)5279.6 WDrop High
120 mm²269 A210 A19.31 V (4.65%)395.7 V31.84 V (7.67%)4179.7 W~ ≤5%
150 mm²309 A241 A15.44 V (3.72%)399.6 V25.48 V (6.14%)3343.8 W~ ≤5%
185 mm²353 A275 A12.52 V (3.02%)402.5 V20.66 V (4.98%)2711.1 W~ ≤5%
240 mm²415 A324 A9.65 V (2.33%)405.3 V15.92 V (3.84%)2089.8 W✓ OK (≤3%)
300 mm²477 A372 A7.72 V (1.86%)407.3 V12.74 V (3.07%)1671.9 W✓ OK (≤3%)
400 mm²570 A445 A5.79 V (1.4%)409.2 V9.55 V (2.3%)1253.9 W✓ OK (≤3%)

FAQ — 125 Amp Cable Size at 500 Meters (415V Three-Phase (UK / Australia Industrial))

What mm² cable size is required for 125A at 500 meters (415V)?

According to IEC 60364-5-52 ampacity and the 3% maximum voltage drop standard, you need 240 mm² copper cable for 125A over 500m at 415V (voltage drop: 9.65V or 2.33%).

What is the power capacity of 125A at 415V?

At unity power factor, 125A at 415V supports 89.85 kW with a standard 125A circuit breaker.