⚡ 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

550 Amp Cable Size at 20 Meters (400V Three-Phase (IEC European Grid))

IEC 60364-5-52 metric conductor sizing (mm²), voltage drop, and power loss calculation for 550 A over 20 m (65.6 ft).

Copper Cable (≤3% Drop)400 mm²Drop: 1.02V (0.25%)
Aluminum Cable (≤3% Drop)400 mm²Drop: 1.68V (0.42%)
Voltage at Load399.0 VLine Loss: 971.0 W
Max Power & Breaker381.05 kW600A MCB/MCCB

IEC 60364 Cable Cross-Section Table (1.5 mm² – 400 mm²) for 550A at 20m

Cross-Section (mm²)Cu AmpacityAl Ampacity Cu Voltage DropLoad VoltageAl Voltage DropPower LossStatus
1.5 mm²16 A12 A271.82 V (67.95%)128.2 V448.37 V (112.09%)258940.0 WDrop High
2.5 mm²24 A18 A163.09 V (40.77%)236.9 V269.02 V (67.26%)155364.0 WDrop High
4 mm²32 A25 A101.93 V (25.48%)298.1 V168.14 V (42.03%)97102.5 WDrop High
6 mm²41 A32 A67.95 V (16.99%)332.0 V112.09 V (28.02%)64735.0 WDrop High
10 mm²57 A44 A40.77 V (10.19%)359.2 V67.26 V (16.81%)38841.0 WDrop High
16 mm²76 A59 A25.48 V (6.37%)374.5 V42.03 V (10.51%)24275.6 WDrop High
25 mm²101 A78 A16.31 V (4.08%)383.7 V26.9 V (6.73%)15536.4 WDrop High
35 mm²125 A97 A11.65 V (2.91%)388.4 V19.22 V (4.8%)11097.4 WDrop High
50 mm²151 A118 A8.15 V (2.04%)391.8 V13.45 V (3.36%)7768.2 WDrop High
70 mm²192 A150 A5.82 V (1.46%)394.2 V9.61 V (2.4%)5548.7 WDrop High
95 mm²232 A181 A4.29 V (1.07%)395.7 V7.08 V (1.77%)4088.5 WDrop High
120 mm²269 A210 A3.4 V (0.85%)396.6 V5.6 V (1.4%)3236.8 WDrop High
150 mm²309 A241 A2.72 V (0.68%)397.3 V4.48 V (1.12%)2589.4 WDrop High
185 mm²353 A275 A2.2 V (0.55%)397.8 V3.64 V (0.91%)2099.5 WDrop High
240 mm²415 A324 A1.7 V (0.42%)398.3 V2.8 V (0.7%)1618.4 WDrop High
300 mm²477 A372 A1.36 V (0.34%)398.6 V2.24 V (0.56%)1294.7 WDrop High
400 mm²570 A445 A1.02 V (0.25%)399.0 V1.68 V (0.42%)971.0 W✓ OK (≤3%)

FAQ — 550 Amp Cable Size at 20 Meters (400V Three-Phase (IEC European Grid))

What mm² cable size is required for 550A at 20 meters (400V)?

According to IEC 60364-5-52 ampacity and the 3% maximum voltage drop standard, you need 400 mm² copper cable for 550A over 20m at 400V (voltage drop: 1.02V or 0.25%).

What is the power capacity of 550A at 400V?

At unity power factor, 550A at 400V supports 381.05 kW with a standard 600A circuit breaker.