⚡ 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

20 Amp Cable Size at 80 Meters (690V Three-Phase (Wind / Heavy Industrial))

IEC 60364-5-52 metric conductor sizing (mm²), voltage drop, and power loss calculation for 20 A over 80 m (262.5 ft).

Copper Cable (≤3% Drop)4 mm²Drop: 14.83V (2.15%)
Aluminum Cable (≤3% Drop)6 mm²Drop: 16.3V (2.36%)
Voltage at Load675.2 VLine Loss: 513.6 W
Max Power & Breaker23.9 kW20A MCB/MCCB

IEC 60364 Cable Cross-Section Table (1.5 mm² – 400 mm²) for 20A at 80m

Cross-Section (mm²)Cu AmpacityAl Ampacity Cu Voltage DropLoad VoltageAl Voltage DropPower LossStatus
1.5 mm²16 A12 A39.54 V (5.73%)650.5 V65.22 V (9.45%)1369.6 WDrop High
2.5 mm²24 A18 A23.72 V (3.44%)666.3 V39.13 V (5.67%)821.8 W~ ≤5%
4 mm²32 A25 A14.83 V (2.15%)675.2 V24.46 V (3.54%)513.6 W✓ OK (≤3%)
6 mm²41 A32 A9.88 V (1.43%)680.1 V16.3 V (2.36%)342.4 W✓ OK (≤3%)
10 mm²57 A44 A5.93 V (0.86%)684.1 V9.78 V (1.42%)205.4 W✓ OK (≤3%)
16 mm²76 A59 A3.71 V (0.54%)686.3 V6.11 V (0.89%)128.4 W✓ OK (≤3%)
25 mm²101 A78 A2.37 V (0.34%)687.6 V3.91 V (0.57%)82.2 W✓ OK (≤3%)
35 mm²125 A97 A1.69 V (0.25%)688.3 V2.8 V (0.41%)58.7 W✓ OK (≤3%)
50 mm²151 A118 A1.19 V (0.17%)688.8 V1.96 V (0.28%)41.1 W✓ OK (≤3%)
70 mm²192 A150 A0.85 V (0.12%)689.2 V1.4 V (0.2%)29.3 W✓ OK (≤3%)
95 mm²232 A181 A0.62 V (0.09%)689.4 V1.03 V (0.15%)21.6 W✓ OK (≤3%)
120 mm²269 A210 A0.49 V (0.07%)689.5 V0.82 V (0.12%)17.1 W✓ OK (≤3%)
150 mm²309 A241 A0.4 V (0.06%)689.6 V0.65 V (0.09%)13.7 W✓ OK (≤3%)
185 mm²353 A275 A0.32 V (0.05%)689.7 V0.53 V (0.08%)11.1 W✓ OK (≤3%)
240 mm²415 A324 A0.25 V (0.04%)689.8 V0.41 V (0.06%)8.6 W✓ OK (≤3%)
300 mm²477 A372 A0.2 V (0.03%)689.8 V0.33 V (0.05%)6.8 W✓ OK (≤3%)
400 mm²570 A445 A0.15 V (0.02%)689.9 V0.24 V (0.04%)5.1 W✓ OK (≤3%)

FAQ — 20 Amp Cable Size at 80 Meters (690V Three-Phase (Wind / Heavy Industrial))

What mm² cable size is required for 20A at 80 meters (690V)?

According to IEC 60364-5-52 ampacity and the 3% maximum voltage drop standard, you need 4 mm² copper cable for 20A over 80m at 690V (voltage drop: 14.83V or 2.15%).

What is the power capacity of 20A at 690V?

At unity power factor, 20A at 690V supports 23.9 kW with a standard 20A circuit breaker.