Weird experience with fuses

[ninjatek 10+ year member]

I have the two amps in my sig

The mono amp has two 30amp fuses, and the 4channel has 2 20amp fuses. I have a 1000watt rms power kit from Lighting Audio, using 4gauge power wire as the main wire, which goes to a distrubution block, which splits off into dual 8 guage wires, that feed to a fuseblock with 2 60 amp fuses. Same with the ground, 4 guage wire, which runs to a distro block which then branches off to 2 8 guage grounds.. it all looks like high qualilty wire.

With the mono amp, I'm not blowing fuses, but eventually the amp will go into protect, and it will stay there until I replace the fuse. The fuse won't be blown, but I will see alot of "residue" on it.. I've tried various brands of fuses and its the same story.

it doesn't happen all the time, as I just went about 3 months w/o replacing the fuses, but it just happened again and I'm wondering "wtf"

anybody with more experience/knowledge care to chime in? I'm starting to wonder if I don't have an adequate ground, because a few days ago I installed new components, and have since bridged my 4 channel amp causing it to draw more power. After about 10 minutes at high volume (no distortion) the amp is going into protect. It will come right back up if I turn down the volume.. If I let it cool for a few minutes, I can do it again for 10 minutes then it goes back into protect... Without letting it cool down, if I quickly pop in a new fuse (i shut the car down lol), it seems to go longer before shutting down again..

Could a bad ground cause these problems? Like the amps can't discharge heat through the ground well enough?

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[btlking 10+ year member]

will it only turn back on if you replace the fuse or can you just turn everything off and back on?

 

[ninjatek 10+ year member]

will it only turn back on if you replace the fuse or can you just turn everything off and back on?

2 different situations. the mono amp will only turn back on if I replace the fuse. but the fuse isn't blown, i can turn around and put the fuse into the fuseholder of the 4 channel amp and that amp works fine.

with the 4 channel amp, it goes into protect, and will come right back up if I turn the volume down. But if I turn the volume down to bring it back up, then crank it right away, it goes back down. If it goes into protect and QUICKLY I turn my car off, replace the fuse, and start the car, I can get another 10 minutes of cranked volume... it seems that replacing the fuse seems to extend the time before going into protect...

the previous owner of the car, who is a car audio buff, says it could be the passive crossovers from the components.. while the set is rated at 4ohms, which is what I want, he thinks just having the coils in the electrical path before getting to the speakers, even though its a 4 ohm load, is still enough to cause it..

he is trying to convince me to go active, but right now, my HU doesn't support running the active setup from the HU ( so i need to by another controller) and I really can't afford that and another amp when if I could just get this setup right I'd be more than happy

 

[ninjatek 10+ year member]

bmp

 

[helotaxi 5,000+ posts]

You're pulling more than the current rating for the fuse but not enough to cleanly blow it. The fuse is still passing current but the resistance of the fuse has gotten high enough that the voltage drops enough to send the amp into undervoltage protection. Replace the fuse with an 80A and you shouldn't have trouble any more. With the 4 channesl you're probably heating the fusee holder and the fuse up and changing the electrical properties of it as well. Turn down the gains on the 4 channel and it might help you out a lot.