Ever seen fuses melt, without blowing?

[headless 10+ year member]

So my front speakers just stopped mid-playing yesterday. I took out the 4150xxk to check fuses (it was playing at a reasonably high volume, though not max, at the time it stopped)...the amp had 3 25amp fuses in it, all 3 were...melted. The plastic was just completely melted. The fuses themselves didn't look blown, they were intact as far as I could see. Anyone else seen this before? The boggling part for me is that the amp stopped turning on even though the fuses hadn't actually broken their contact. Replacing the fuses did fix the problem; it powers up now. Maybe there was unusually high resistence through the fuses and the amp just doesn't turn on in that case? Boggle.

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[lowriderram_95 10+ year member]

that happened on my friends tacoma. although it was the fuse at the battery. the fuse and fuse holder melted together yet didn't blow the fuse and the **** thing still works.

 

[herbykw 10+ year member]

I have a Phoenix Gold XS6600 that does that. It did it right before the sub channel burnt out.

 

[amartin_72]

Ive never seen that

 

[BassAddictJ 5,000+ posts]

ive seen it.

 

[2lo2flo 10+ year member]

Happens all the time to me with my Orion hcca 250G4, the hcca g4 line has a reputation for "melting fuses"

 

[bigaudiofanati2 10+ year member]

I have been wounding about this, like reading thread after thread about how the fuse didnt blow, weather it be the main fuse or a amp fuse. Is it because there just not made properly or that there are better ones than others or what?

 

[only126db 10+ year member]

Modify the amp to accept Maxi fuses or to run with outboard Maxi fuses and you shouldn't have that problem again.

 

[MohonsCustomAud 10+ year member]

I have seen this numerous times in my shop. To my belief there is a few rfeasons that would cause this.

1) Crappy Ground

2) crappy Connection between the wire in the connestor, and the actual inside of the fuse holder where the fuse goes not making a good connection with the fuse

3) the best one i have seen, is that crappy copper clad aluminum wire burining up the fuse holder and the wire.

Most of the times i have seen this, it normally occurs on the output side of the fuse holder. The above reasons is my own observation. I am pretty sure that there is way more to it than that.

 

[bigaudiofanati2 10+ year member]

One reason I use di electric grease on the connectors and all.

 

[headless 10+ year member]

Crazy; well, it's nice to know i'm not alone at least.

The amp sounds fine and hasn't had any recurring problems... very strange.

FIWIW, the possibility of a bad ground or bad power wire is pretty low; i've got 2x4ga run from my rear battery to a ground that was properly prepared and is still snug and metering a very low resistance. The runs of 4ga from my rear batt are only 4 feet long and are not corroded or anything...i haven't metered them, but they look good and once i replaced the fuses in the amp the same runs of wire are running it OK now.

The confusing part to me was that the fuses didn't appear blown...but the amp did stop powering on. Boggle. maybe the melted fuse holders were allowing power to arc from the fuses to another component or the frame? No burning smell and none of the components looks scorched.

 

[headless 10+ year member]

I have been wounding about this, like reading thread after thread about how the fuse didnt blow, weather it be the main fuse or a amp fuse. Is it because there just not made properly or that there are better ones than others or what?

Fuses aren't an instant-off type situation. They blow if the current flowing through them is significantly above their amp rating - for a period of time. The trick is that some fuses are designed to blow faster than others. In any case, there are momentary spikes of power usage that in many cases exceed the amp's fused rating and yet won't blow the fuse unless they are sustained for more than a moment. This site has a pretty good explanation:

http://www.tpub.com/content/neets/14175/css/14175_94.htm

It makes sense to me that these little ass 25amp fuses that they put inside the amp would get hot if i'm pulling a steady 50-70 amps through them for a long period of time (hours...)...they are pretty thin metal paths for the power to take and i'm sure that much power going through them generates a lot of heat. The 4150xxk pulls a peak of 82amps according to specs. That's gotta generate some heat travelling through 3 micro fuses. I just didn't expect the ****ing plastic cases to melt.

 

[grooverider 10+ year member]

its called using the WRONG SIZED FUSE

 

[headless 10+ year member]

its called using the WRONG SIZED FUSE

Nice. Aren't you just a condescending douchebag who doesn't read nor know what he is talking about then? Thanks dude. Lets put some 15a fuses in there so that they blow when the amp starts playing at 3/4 of it's max volume. That'd fix it up real good, right? LOL.

Well, I guess arc should change the fuse recommendations for their amps just because you think they should be a different rating - their specs say 3x25a fuses should be used and that's what was in the amp. 3x25a is a perfect match for the 82amp max pull of the amp.

http://ampguts.realmofexcursion.com/Arc_4150XXK/

 

[sundownz Pro Seller]

Yes, have seen it several times. Usually from fuses getting loose.