⚡ 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

25 Amp Cable Size at 15 Meters (400V Three-Phase (IEC European Grid))

IEC 60364-5-52 metric conductor sizing (mm²), voltage drop, and power loss calculation for 25 A over 15 m (49.2 ft).

Copper Cable (≤3% Drop)4 mm²Drop: 3.47V (0.87%)
Aluminum Cable (≤3% Drop)4 mm²Drop: 5.73V (1.43%)
Voltage at Load396.5 VLine Loss: 150.5 W
Max Power & Breaker17.32 kW25A MCB/MCCB

IEC 60364 Cable Cross-Section Table (1.5 mm² – 400 mm²) for 25A at 15m

Cross-Section (mm²)Cu AmpacityAl Ampacity Cu Voltage DropLoad VoltageAl Voltage DropPower LossStatus
1.5 mm²16 A12 A9.27 V (2.32%)390.7 V15.29 V (3.82%)401.2 WDrop High
2.5 mm²24 A18 A5.56 V (1.39%)394.4 V9.17 V (2.29%)240.8 WDrop High
4 mm²32 A25 A3.47 V (0.87%)396.5 V5.73 V (1.43%)150.5 W✓ OK (≤3%)
6 mm²41 A32 A2.32 V (0.58%)397.7 V3.82 V (0.96%)100.3 W✓ OK (≤3%)
10 mm²57 A44 A1.39 V (0.35%)398.6 V2.29 V (0.57%)60.2 W✓ OK (≤3%)
16 mm²76 A59 A0.87 V (0.22%)399.1 V1.43 V (0.36%)37.6 W✓ OK (≤3%)
25 mm²101 A78 A0.56 V (0.14%)399.4 V0.92 V (0.23%)24.1 W✓ OK (≤3%)
35 mm²125 A97 A0.4 V (0.1%)399.6 V0.66 V (0.16%)17.2 W✓ OK (≤3%)
50 mm²151 A118 A0.28 V (0.07%)399.7 V0.46 V (0.11%)12.0 W✓ OK (≤3%)
70 mm²192 A150 A0.2 V (0.05%)399.8 V0.33 V (0.08%)8.6 W✓ OK (≤3%)
95 mm²232 A181 A0.15 V (0.04%)399.9 V0.24 V (0.06%)6.3 W✓ OK (≤3%)
120 mm²269 A210 A0.12 V (0.03%)399.9 V0.19 V (0.05%)5.0 W✓ OK (≤3%)
150 mm²309 A241 A0.09 V (0.02%)399.9 V0.15 V (0.04%)4.0 W✓ OK (≤3%)
185 mm²353 A275 A0.08 V (0.02%)399.9 V0.12 V (0.03%)3.3 W✓ OK (≤3%)
240 mm²415 A324 A0.06 V (0.01%)399.9 V0.1 V (0.02%)2.5 W✓ OK (≤3%)
300 mm²477 A372 A0.05 V (0.01%)400.0 V0.08 V (0.02%)2.0 W✓ OK (≤3%)
400 mm²570 A445 A0.03 V (0.01%)400.0 V0.06 V (0.01%)1.5 W✓ OK (≤3%)

FAQ — 25 Amp Cable Size at 15 Meters (400V Three-Phase (IEC European Grid))

What mm² cable size is required for 25A at 15 meters (400V)?

According to IEC 60364-5-52 ampacity and the 3% maximum voltage drop standard, you need 4 mm² copper cable for 25A over 15m at 400V (voltage drop: 3.47V or 0.87%).

What is the power capacity of 25A at 400V?

At unity power factor, 25A at 400V supports 17.32 kW with a standard 25A circuit breaker.