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

300 Amp Cable Size at 45 Meters (690V Three-Phase (Wind / Heavy Industrial))

IEC 60364-5-52 metric conductor sizing (mm²), voltage drop, and power loss calculation for 300 A over 45 m (147.6 ft).

Copper Cable (≤3% Drop)150 mm²Drop: 3.34V (0.48%)
Aluminum Cable (≤3% Drop)240 mm²Drop: 3.44V (0.5%)
Voltage at Load686.7 VLine Loss: 1733.4 W
Max Power & Breaker358.53 kW300A MCB/MCCB

IEC 60364 Cable Cross-Section Table (1.5 mm² – 400 mm²) for 300A at 45m

Cross-Section (mm²)Cu AmpacityAl Ampacity Cu Voltage DropLoad VoltageAl Voltage DropPower LossStatus
1.5 mm²16 A12 A333.59 V (48.35%)356.4 V550.27 V (79.75%)173340.0 WDrop High
2.5 mm²24 A18 A200.16 V (29.01%)489.8 V330.16 V (47.85%)104004.0 WDrop High
4 mm²32 A25 A125.1 V (18.13%)564.9 V206.35 V (29.91%)65002.5 WDrop High
6 mm²41 A32 A83.4 V (12.09%)606.6 V137.57 V (19.94%)43335.0 WDrop High
10 mm²57 A44 A50.04 V (7.25%)640.0 V82.54 V (11.96%)26001.0 WDrop High
16 mm²76 A59 A31.27 V (4.53%)658.7 V51.59 V (7.48%)16250.6 WDrop High
25 mm²101 A78 A20.02 V (2.9%)670.0 V33.02 V (4.78%)10400.4 WDrop High
35 mm²125 A97 A14.3 V (2.07%)675.7 V23.58 V (3.42%)7428.9 WDrop High
50 mm²151 A118 A10.01 V (1.45%)680.0 V16.51 V (2.39%)5200.2 WDrop High
70 mm²192 A150 A7.15 V (1.04%)682.9 V11.79 V (1.71%)3714.4 WDrop High
95 mm²232 A181 A5.27 V (0.76%)684.7 V8.69 V (1.26%)2736.9 WDrop High
120 mm²269 A210 A4.17 V (0.6%)685.8 V6.88 V (1.0%)2166.7 WDrop High
150 mm²309 A241 A3.34 V (0.48%)686.7 V5.5 V (0.8%)1733.4 W✓ OK (≤3%)
185 mm²353 A275 A2.7 V (0.39%)687.3 V4.46 V (0.65%)1405.5 W✓ OK (≤3%)
240 mm²415 A324 A2.08 V (0.3%)687.9 V3.44 V (0.5%)1083.4 W✓ OK (≤3%)
300 mm²477 A372 A1.67 V (0.24%)688.3 V2.75 V (0.4%)866.7 W✓ OK (≤3%)
400 mm²570 A445 A1.25 V (0.18%)688.7 V2.06 V (0.3%)650.0 W✓ OK (≤3%)

FAQ — 300 Amp Cable Size at 45 Meters (690V Three-Phase (Wind / Heavy Industrial))

What mm² cable size is required for 300A at 45 meters (690V)?

According to IEC 60364-5-52 ampacity and the 3% maximum voltage drop standard, you need 150 mm² copper cable for 300A over 45m at 690V (voltage drop: 3.34V or 0.48%).

What is the power capacity of 300A at 690V?

At unity power factor, 300A at 690V supports 358.53 kW with a standard 300A circuit breaker.