Fuse Sizing Calculator

Calculate the correct fuse or circuit breaker rating for your DC installation. Fuses protect your cables from overheating and should be sized to the cable, not the load.

Enter Your Values

Results

Enter your values and click Calculate to see results.

How Fuse Sizing Works

A fuse protects the cable, not the equipment. It must blow before the cable overheats. The fuse rating should be:

  • Higher than the expected load current (so it doesn't blow in normal operation)
  • Lower than the cable's maximum current rating (so it protects the cable)

Load Current < Fuse Rating < Cable Max Current

We recommend MEGA-fuses for high-current DC applications and quality fuse holders for proper installation.

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