⚡ 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

425 Amp Cable Size at 40 Meters (415V Three-Phase (UK / Australia Industrial))

IEC 60364-5-52 metric conductor sizing (mm²), voltage drop, and power loss calculation for 425 A over 40 m (131.2 ft).

Copper Cable (≤3% Drop)300 mm²Drop: 2.1V (0.51%)
Aluminum Cable (≤3% Drop)400 mm²Drop: 2.6V (0.63%)
Voltage at Load412.9 VLine Loss: 1546.1 W
Max Power & Breaker305.49 kW450A MCB/MCCB

IEC 60364 Cable Cross-Section Table (1.5 mm² – 400 mm²) for 425A at 40m

Cross-Section (mm²)Cu AmpacityAl Ampacity Cu Voltage DropLoad VoltageAl Voltage DropPower LossStatus
1.5 mm²16 A12 A420.08 V (101.22%)0.0 V692.94 V (166.97%)309230.0 WDrop High
2.5 mm²24 A18 A252.05 V (60.73%)163.0 V415.76 V (100.18%)185538.0 WDrop High
4 mm²32 A25 A157.53 V (37.96%)257.5 V259.85 V (62.61%)115961.2 WDrop High
6 mm²41 A32 A105.02 V (25.31%)310.0 V173.23 V (41.74%)77307.5 WDrop High
10 mm²57 A44 A63.01 V (15.18%)352.0 V103.94 V (25.05%)46384.5 WDrop High
16 mm²76 A59 A39.38 V (9.49%)375.6 V64.96 V (15.65%)28990.3 WDrop High
25 mm²101 A78 A25.2 V (6.07%)389.8 V41.58 V (10.02%)18553.8 WDrop High
35 mm²125 A97 A18.0 V (4.34%)397.0 V29.7 V (7.16%)13252.7 WDrop High
50 mm²151 A118 A12.6 V (3.04%)402.4 V20.79 V (5.01%)9276.9 WDrop High
70 mm²192 A150 A9.0 V (2.17%)406.0 V14.85 V (3.58%)6626.4 WDrop High
95 mm²232 A181 A6.63 V (1.6%)408.4 V10.94 V (2.64%)4882.6 WDrop High
120 mm²269 A210 A5.25 V (1.27%)409.7 V8.66 V (2.09%)3865.4 WDrop High
150 mm²309 A241 A4.2 V (1.01%)410.8 V6.93 V (1.67%)3092.3 WDrop High
185 mm²353 A275 A3.41 V (0.82%)411.6 V5.62 V (1.35%)2507.3 WDrop High
240 mm²415 A324 A2.63 V (0.63%)412.4 V4.33 V (1.04%)1932.7 WDrop High
300 mm²477 A372 A2.1 V (0.51%)412.9 V3.46 V (0.83%)1546.1 W✓ OK (≤3%)
400 mm²570 A445 A1.58 V (0.38%)413.4 V2.6 V (0.63%)1159.6 W✓ OK (≤3%)

FAQ — 425 Amp Cable Size at 40 Meters (415V Three-Phase (UK / Australia Industrial))

What mm² cable size is required for 425A at 40 meters (415V)?

According to IEC 60364-5-52 ampacity and the 3% maximum voltage drop standard, you need 300 mm² copper cable for 425A over 40m at 415V (voltage drop: 2.1V or 0.51%).

What is the power capacity of 425A at 415V?

At unity power factor, 425A at 415V supports 305.49 kW with a standard 450A circuit breaker.