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Cable sizing

Calculate the right cable cross-section based on voltage, current, length and permitted voltage drop. Supports 12/24/48 V DC as well as single- and three-phase AC.

Enter the actual one-way cable length — we account for the return path in DC and single-phase.

Guideline: 3 % for critical circuits (charging, inverter), 5 % for lighting.

Recommended cross-section

mm²

The smallest standard cross-section that meets both voltage-drop and current-load requirements, with a 25% margin for continuous loads (SS 436 / ABYC E-11).

Voltage drop

Power loss

Ampacity

Fuse

Compare all cross-sections

Green tick = meets the requirements. Red cross = undersized.

Cross-sectionVoltage dropLossMax currentVoltage drop OKCurrent OK

Guideline values for copper cable with PVC insulation (70 °C), installed individually in free air. Actual sizing may need to account for installation method, grouping, ambient temperature and applicable standards (SS 436 40 00 / ABYC). Use this tool as guidance, not as a final specification.

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Seen something odd or wrong? Describe briefly what happened — we email it straight to our bug team (bug@kraftur.se).

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