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Electrical power/ CALCULATOR

DC cable area for a voltage-drop target

Estimate the copper conductor area needed to keep steady DC voltage drop below a chosen percentage.

Measure from the source to the load; the return conductor is included by the formula.
Use the realistic continuous current at the lowest relevant operating voltage.
Use the voltage basis for the permitted percentage drop.
A project target, not a substitute for an applicable wiring requirement.
Allowed cable voltage drop

0.96 V

Minimum area from voltage drop only

14.58 mm²

Next area in the screening list

16.0 mm²

Drop at the listed area

0.88 V

Drop at the listed area

1.82 %

Cable heat loss at the listed area

70.0 W

Interpretation:Voltage drop alone requires at least 14.58 mm²; the next area in this screening list is 16 mm², with about 1.82% drop and 70 W of cable heat. Verify ampacity, protection and installation rules separately.

Copper resistivity 0.0175 Ω·mm²/m at a reference temperature, equal outgoing and return conductors, steady DC current and a generic metric area list. Temperature, connection resistance, conductor ampacity, insulation, bundling, terminals, fuses, fault current and local rules are excluded. The listed area is a voltage-drop screen, never a complete cable selection.

Continue your calculation

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