⚡ 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

125 Amp Cable Size at 5 Meters (24V DC (Off-Grid Solar / Industrial Control))

IEC 60364-5-52 metric conductor sizing (mm²), voltage drop, and power loss calculation for 125 A over 5 m (16.4 ft).

Copper Cable (≤3% Drop)50 mm²Drop: 0.54V (2.23%)
Aluminum Cable (≤3% Drop)70 mm²Drop: 0.63V (2.63%)
Voltage at Load23.5 VLine Loss: 66.9 W
Max Power & Breaker3.0 kW125A MCB/MCCB

IEC 60364 Cable Cross-Section Table (1.5 mm² – 400 mm²) for 125A at 5m

Cross-Section (mm²)Cu AmpacityAl Ampacity Cu Voltage DropLoad VoltageAl Voltage DropPower LossStatus
1.5 mm²16 A12 A17.83 V (74.31%)6.2 V29.42 V (122.57%)2229.2 WDrop High
2.5 mm²24 A18 A10.7 V (44.58%)13.3 V17.65 V (73.54%)1337.5 WDrop High
4 mm²32 A25 A6.69 V (27.86%)17.3 V11.03 V (45.96%)835.9 WDrop High
6 mm²41 A32 A4.46 V (18.58%)19.5 V7.35 V (30.64%)557.3 WDrop High
10 mm²57 A44 A2.67 V (11.15%)21.3 V4.41 V (18.39%)334.4 WDrop High
16 mm²76 A59 A1.67 V (6.97%)22.3 V2.76 V (11.49%)209.0 WDrop High
25 mm²101 A78 A1.07 V (4.46%)22.9 V1.76 V (7.35%)133.8 WDrop High
35 mm²125 A97 A0.76 V (3.18%)23.2 V1.26 V (5.25%)95.5 W~ ≤5%
50 mm²151 A118 A0.54 V (2.23%)23.5 V0.88 V (3.68%)66.9 W✓ OK (≤3%)
70 mm²192 A150 A0.38 V (1.59%)23.6 V0.63 V (2.63%)47.8 W✓ OK (≤3%)
95 mm²232 A181 A0.28 V (1.17%)23.7 V0.46 V (1.94%)35.2 W✓ OK (≤3%)
120 mm²269 A210 A0.22 V (0.93%)23.8 V0.37 V (1.53%)27.9 W✓ OK (≤3%)
150 mm²309 A241 A0.18 V (0.74%)23.8 V0.29 V (1.23%)22.3 W✓ OK (≤3%)
185 mm²353 A275 A0.14 V (0.6%)23.9 V0.24 V (0.99%)18.1 W✓ OK (≤3%)
240 mm²415 A324 A0.11 V (0.46%)23.9 V0.18 V (0.77%)13.9 W✓ OK (≤3%)
300 mm²477 A372 A0.09 V (0.37%)23.9 V0.15 V (0.61%)11.1 W✓ OK (≤3%)
400 mm²570 A445 A0.07 V (0.28%)23.9 V0.11 V (0.46%)8.4 W✓ OK (≤3%)

FAQ — 125 Amp Cable Size at 5 Meters (24V DC (Off-Grid Solar / Industrial Control))

What mm² cable size is required for 125A at 5 meters (24V)?

According to IEC 60364-5-52 ampacity and the 3% maximum voltage drop standard, you need 50 mm² copper cable for 125A over 5m at 24V (voltage drop: 0.54V or 2.23%).

What is the power capacity of 125A at 24V?

At unity power factor, 125A at 24V supports 3.0 kW with a standard 125A circuit breaker.