How big should the fuse be?
If you’re installing just one amplifier, the fuse at the battery should simply match or slightly exceed the fuse rating of the amplifier itself. If you’re installing two or more amplifiers, just add their fuse ratings together and install a fuse rated roughly equal to this sum. Generally, it’s better to go slightly higher than lower, but a margin of five amperes is acceptable. Say you have three amplifiers, two with fuse ratings of 20 amps each and one with a fuse rating of 25 amps. In this case, you can safely go with either a 60 or 70 amp fuse. (Of course, if your system is powerful enough to demand that you install a heavy duty fuse, it’s important that your power and ground wire be of an appropriately heavy gauge as well.
If you’re installing just one amplifier, the fuse at the battery should simply match or slightly exceed the fuse rating of the amplifier itself. If you’re installing two or more amplifiers, just add their fuse ratings together and install a fuse rated roughly equal to this sum. Generally, it’s better to go slightly higher than lower, but a margin of five amperes is acceptable. Say you have three amplifiers, two with fuse ratings of 20 amps each and one with a fuse rating of 25 amps. In this case, you can safely go with either a 60 or 70 amp fuse.
