Finster07

Anyone have a link to basic car electrical wiring where it discusses how you determine the gauge wire and size of the fuse based on the amperage draw?

thanks

thoyer

You can do a google search on wire ampacity and lots of sites with charts come up. The fuse is sized to protect the wire so if you have a wire rated for 20 amps, you don't want a 30 amp fuse protecting it. The wire will become the fuse in this case.

Fuses are also sized based on inrush current which is the initial current draw when a circuit is powered. For example, your A/C blower may normally pull 9 amps during operation, but have an inrush of 20 amps when it is first turned on, thus necessitating a 25 amp fuse and the associated wire gauge. This is a very generic example, the duration of the inrush also factors into fuse selection.

Tom