What size fuse should an 800W amp use?

AmBo

Active Member
Feb 3, 2004
1,027
1
36
New Jersey
Hey all! QUick question. On the way home I blew two 40amp fuses on my power line. I'm running an 800W Kenwood amp. The gain is pretty much 0. It wasnt even cranked, just loud and it blew. Should I be running 80?
 
  • Sponsors (?)


AmBo said:
Hey all! QUick question. On the way home I blew two 40amp fuses on my power line. I'm running an 800W Kenwood amp. The gain is pretty much 0. It wasnt even cranked, just loud and it blew. Should I be running 80?

An 80 would be the minimum you should be running. A good rule of thumb to start with is 10 amps/100watts. Sometimes it takes a little more, but that is a good starting point. I have an 80 on my sub amp which just happens to be 800watts and it has never blown a fuse. Knock on wood.
 
wait, where were the fuses located? if you weren't playing it that loud, there's got to be another reason why they blew. and amped turned down on low volume SHOULD NEVER blow fuses unless something is wrong with the power wire.
 
ChaosStarter said:
wait, where were the fuses located? if you weren't playing it that loud, there's got to be another reason why they blew. and amped turned down on low volume SHOULD NEVER blow fuses unless something is wrong with the power wire.

This is correct and I should've stated it, but I only half answered your question. Sorry about that. You may have a bad connection somewhere which will cause you to blow fuses. Check both the power and ground wires. You may have a loose connection or the power wire may be intermittently grounding out. Something else you need to do is look at the blown fuse and see if it's actually blown or if it's melted. If it's melted you are having a voltage problem, which MAY mean that your alternator is not keeping up. In other words your system is pulling more current than your charging system can supply. A fuse will melt under these conditions over time.