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⚡ IEC 60364-5-52 · DIN VDE · NEK 400 · SS 436 40 00

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

IEC 60364-5-52 metric conductor sizing (mm²), voltage drop, and power loss calculation for 80 A over 20 m (65.6 ft).

Copper Cable (≤3% Drop)25 mm²Drop: 2.37V (0.34%)
Aluminum Cable (≤3% Drop)35 mm²Drop: 2.8V (0.41%)
Voltage at Load687.6 VLine Loss: 328.7 W
Max Power & Breaker95.61 kW80A MCB/MCCB

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

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%)5478.4 WDrop High
2.5 mm²24 A18 A23.72 V (3.44%)666.3 V39.13 V (5.67%)3287.0 WDrop High
4 mm²32 A25 A14.83 V (2.15%)675.2 V24.46 V (3.54%)2054.4 WDrop High
6 mm²41 A32 A9.88 V (1.43%)680.1 V16.3 V (2.36%)1369.6 WDrop High
10 mm²57 A44 A5.93 V (0.86%)684.1 V9.78 V (1.42%)821.8 WDrop High
16 mm²76 A59 A3.71 V (0.54%)686.3 V6.11 V (0.89%)513.6 WDrop High
25 mm²101 A78 A2.37 V (0.34%)687.6 V3.91 V (0.57%)328.7 W✓ OK (≤3%)
35 mm²125 A97 A1.69 V (0.25%)688.3 V2.8 V (0.41%)234.8 W✓ OK (≤3%)
50 mm²151 A118 A1.19 V (0.17%)688.8 V1.96 V (0.28%)164.4 W✓ OK (≤3%)
70 mm²192 A150 A0.85 V (0.12%)689.2 V1.4 V (0.2%)117.4 W✓ OK (≤3%)
95 mm²232 A181 A0.62 V (0.09%)689.4 V1.03 V (0.15%)86.5 W✓ OK (≤3%)
120 mm²269 A210 A0.49 V (0.07%)689.5 V0.82 V (0.12%)68.5 W✓ OK (≤3%)
150 mm²309 A241 A0.4 V (0.06%)689.6 V0.65 V (0.09%)54.8 W✓ OK (≤3%)
185 mm²353 A275 A0.32 V (0.05%)689.7 V0.53 V (0.08%)44.4 W✓ OK (≤3%)
240 mm²415 A324 A0.25 V (0.04%)689.8 V0.41 V (0.06%)34.2 W✓ OK (≤3%)
300 mm²477 A372 A0.2 V (0.03%)689.8 V0.33 V (0.05%)27.4 W✓ OK (≤3%)
400 mm²570 A445 A0.15 V (0.02%)689.9 V0.24 V (0.04%)20.5 W✓ OK (≤3%)

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

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

According to IEC 60364-5-52 ampacity and the 3% maximum voltage drop standard, you need 25 mm² copper cable for 80A over 20m at 690V (voltage drop: 2.37V or 0.34%).

What is the power capacity of 80A at 690V?

At unity power factor, 80A at 690V supports 95.61 kW with a standard 80A circuit breaker.