Cable Sizing Guide

Determine the minimum cable cross-section area (CSA) needed for your DC installation based on current draw, cable length, and acceptable voltage drop.

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Results

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How Cable Sizing Works

Undersized cables cause excessive voltage drop, overheating, and potential fire risk. The minimum cable size is calculated from:

Min CSA = (2 × L × I × ρ) / (V × max_drop% / 100)

We then round up to the nearest standard cable size (1.5, 2.5, 4, 6, 10, 16, 25, 35, 50, 70, 95 mm²).

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