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

70 Amp Cable Size at 120 Meters (48V DC (LiFePO4 Battery Bank / Telecom))

IEC 60364-5-52 metric conductor sizing (mm²), voltage drop, and power loss calculation for 70 A over 120 m (393.7 ft).

Copper Cable (≤3% Drop)300 mm²Drop: 1.2V (2.5%)
Aluminum Cable (≤3% Drop)400 mm²Drop: 1.48V (3.09%)
Voltage at Load46.8 VLine Loss: 83.9 W
Max Power & Breaker3.36 kW70A MCB/MCCB

IEC 60364 Cable Cross-Section Table (1.5 mm² – 400 mm²) for 70A at 120m

Cross-Section (mm²)Cu AmpacityAl Ampacity Cu Voltage DropLoad VoltageAl Voltage DropPower LossStatus
1.5 mm²16 A12 A239.68 V (499.33%)0.0 V395.36 V (823.67%)16777.6 WDrop High
2.5 mm²24 A18 A143.81 V (299.6%)0.0 V237.22 V (494.2%)10066.6 WDrop High
4 mm²32 A25 A89.88 V (187.25%)0.0 V148.26 V (308.87%)6291.6 WDrop High
6 mm²41 A32 A59.92 V (124.83%)0.0 V98.84 V (205.92%)4194.4 WDrop High
10 mm²57 A44 A35.95 V (74.9%)12.0 V59.3 V (123.55%)2516.6 WDrop High
16 mm²76 A59 A22.47 V (46.81%)25.5 V37.06 V (77.22%)1572.9 WDrop High
25 mm²101 A78 A14.38 V (29.96%)33.6 V23.72 V (49.42%)1006.7 WDrop High
35 mm²125 A97 A10.27 V (21.4%)37.7 V16.94 V (35.3%)719.0 WDrop High
50 mm²151 A118 A7.19 V (14.98%)40.8 V11.86 V (24.71%)503.3 WDrop High
70 mm²192 A150 A5.14 V (10.7%)42.9 V8.47 V (17.65%)359.5 WDrop High
95 mm²232 A181 A3.78 V (7.88%)44.2 V6.24 V (13.01%)264.9 WDrop High
120 mm²269 A210 A3.0 V (6.24%)45.0 V4.94 V (10.3%)209.7 WDrop High
150 mm²309 A241 A2.4 V (4.99%)45.6 V3.95 V (8.24%)167.8 W~ ≤5%
185 mm²353 A275 A1.94 V (4.05%)46.1 V3.21 V (6.68%)136.0 W~ ≤5%
240 mm²415 A324 A1.5 V (3.12%)46.5 V2.47 V (5.15%)104.9 W~ ≤5%
300 mm²477 A372 A1.2 V (2.5%)46.8 V1.98 V (4.12%)83.9 W✓ OK (≤3%)
400 mm²570 A445 A0.9 V (1.87%)47.1 V1.48 V (3.09%)62.9 W✓ OK (≤3%)

FAQ — 70 Amp Cable Size at 120 Meters (48V DC (LiFePO4 Battery Bank / Telecom))

What mm² cable size is required for 70A at 120 meters (48V)?

According to IEC 60364-5-52 ampacity and the 3% maximum voltage drop standard, you need 300 mm² copper cable for 70A over 120m at 48V (voltage drop: 1.2V or 2.5%).

What is the power capacity of 70A at 48V?

At unity power factor, 70A at 48V supports 3.36 kW with a standard 70A circuit breaker.