Fuse Sizing Calculator

Determine the correct fuse rating based on operating current and safety margin.

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A

Minimum Fuse Rating

6.25 A

Minimum Fuse Rating vs Operating Current

View formula & how it works →

Fuse Sizing

Fuse >= I_operating x Safety_Factor

Standard practice: 1.25 (125%) for continuous loads. Round up to next standard fuse value.

Example Calculation

Circuit draws 5 A normally.

  1. 01Min fuse = 5 x 1.25 = 6.25 A
  2. 02Use a 7 A or 7.5 A standard fuse.

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