DC Wire Gauge & Voltage DropEngineering

DC Wire Gauge, Copper Cross-Section (mm²) & Voltage Drop Calculator

Calculate electrical voltage drop percentage, power loss in Watts, and recommended American Wire Gauge (AWG) or metric mm² copper cable size for 12V, 24V, and 48V DC circuits.

Calculator Inputs

Live Real-Time
A
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m
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Calculated ResultDC Wire Gauge & Voltage Drop

Total Circuit Voltage Drop Percentage

5.83%%

Voltage Lost in Wire (Volts Drop)

0.7 V

Delivered Voltage at Appliance Terminals

11.3 V

Detailed Calculation Breakdown

Lost Voltage Drop
0.7 V
Wire Heat Power Loss
14 Watts
Voltage Drop Ratio
5.83%

Calculation Methodology

Voltage Drop (V) = (2 * One-Way Run Length (m) * Amperage (A) * 0.0175 Copper Resistivity) / Cross-Section Area (mm²). Voltage Drop % = (Vdrop / Vsource) * 100.

Important Legal & Educational Disclaimer

National Electrical Code (NEC) recommends keeping total circuit voltage drop below 3% for critical solar inverters, marine electronics, and battery banks.

This calculator is designed for educational and informational purposes only based on public statutory frameworks. The outputs do not constitute binding financial, tax, or legal advice. We assume no liability for decisions made based on these estimations. Always verify with the relevant official authorities or a certified professional advisor.

Frequently Asked Questions

To deliver the same power (Watts = Volts * Amps), a 12V system draws roughly 20 times more current (Amps) than a 240V system. High amperage creates dramatic resistance voltage drop unless wire gauge is large.
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