Fuse question from a noob

[Xjeff 10+ year member]

Ok to start it off I need to explain why I want to know the answer. I didn't vetch my car on fire or blow a fuse or anything, I was expecting to blow and fuse and was wondering why it didn't. More of learning than problem shooting later down the road //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif ok so I just hooked up my sa-12 on my hif1500d running about 1000k rms to it and it pounds very happy. But I figured I would have blown my 100a anl fuse on my 0gauge power wire by my battery but it didn't, again no problem with nothing that isn't broke //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif and I didn't blow the 50a anl fuse at my distro block to 4gauge wire to amp. I was figuring I was going to be pulling more than 100a at the power wire with my other amp added in as well but it seems to be holding. My question really is why didn't my fuse blow? Well I know the stupid answer is "because your not drawing more than 100a" but can anyone clear things up it me a little? I did order some 250a fuses for my 0gauage and some 150a for my 4 gauge wire cus I figured I would have blow my other ones on the first song I played lol. I'm going to work so I won't be back for a few hours if you have any more questions ill be more than willing to answer them in a few hours. Thanks to everyone how can shed some light for me.

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[av83 10+ year member]

Ok to start it off I need to explain why I want to know the answer. I didn't vetch my car on fire or blow a fuse or anything, I was expecting to blow and fuse and was wondering why it didn't. More of learning than problem shooting later down the road //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif ok so I just hooked up my sa-12 on my hif1500d running about 1000k rms to it and it pounds very happy. But I figured I would have blown my 100a anl fuse on my 0gauge power wire by my battery but it didn't, again no problem with nothing that isn't broke //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif and I didn't blow the 50a anl fuse at my distro block to 4gauge wire to amp. I was figuring I was going to be pulling more than 100a at the power wire with my other amp added in as well but it seems to be holding. My question really is why didn't my fuse blow? Well I know the stupid answer is "because your not drawing more than 100a" but can anyone clear things up it me a little? I did order some 250a fuses for my 0gauage and some 150a for my 4 gauge wire cus I figured I would have blow my other ones on the first song I played lol. I'm going to work so I won't be back for a few hours if you have any more questions ill be more than willing to answer them in a few hours. Thanks to everyone how can shed some light for me.

You answered it correctly yourself. Plus, a fuse can take a little bit over its rating for a bit. A short would blow it quickly, but drawing over its rating isn't going to be an instantaneous break, most of the time. I've melted fuses by drawing too much, without breaking the filament.

 

[TheUnderFighter 10+ year member]

tl;dr

But you fuse for the wire. CCA 0 gauge you use a 250a fuse. OFC 0 gauge you use a 300a fuse.

 

[frogcase2002 10+ year member]

Well even if you draw more than 100 its not always going to blow because its only drawing the Max for fractions of a sec..sometimes they will even start to melt before they would blow. I have used 150amp fuses with my 3000rms

You should be happy. Most peoples questions about fuses are they don't know why there blowing lol

 

[frogcase2002 10+ year member]

tl;dr
But you fuse for the wire. CCA 0 gauge you use a 250a fuse. OFC 0 gauge you use a 300a fuse.

If that's what you wanna do. I have never used a 300 and I have 2 runs of ofc 0. I have always used a little less amp fuse than i think so if anything messes up its going to be the fuse blowing

 

[Xjeff 10+ year member]

Ok thanks figured I kinda answers my own question just making sure. Should I still pop in the higher fuses? Or just save them if I blow my current ones?

 

[dumpbeast86 10+ year member]

If that's what you wanna do. I have never used a 300 and I have 2 runs of ofc 0. I have always used a little less amp fuse than i think so if anything messes up its going to be the fuse blowing

^^this. You don't always fuse for the wire. some amps are rated below the wire rating, the first thing in line to blow will be the amp, not the fuse. if your amp is rated over 300, then yeah, fuse your 1/0 for 300.

 

[frogcase2002 10+ year member]

Ok thanks figured I kinda answers my own question just making sure. Should I still pop in the higher fuses? Or just save them if I blow my current ones?

I would just keep what you got in for now. Don't wanna fix what's not broke lol

 

[gckless 5,000+ posts]

If that's what you wanna do. I have never used a 300 and I have 2 runs of ofc 0. I have always used a little less amp fuse than i think so if anything messes up its going to be the fuse blowing

That's fine if you're well under the capacity of your wire. But if you have 2 amps capable of drawing just under what your wire is rated for, then you may blow that fuse each time you turn up the volume. If you run a second fuse for the amp, then what you said makes sense. Each situation is different.

 

[dumpbeast86 10+ year member]

btw op, your math probably wasn't wrong in trying to determine your current draw, if that's what you did. truth is, those numbers only stick in a perfect world situation. that's the right way to determine all the equipment you need, but once you factor in all the little different variables and conditions in each particular setup, your actual "operational draw" might be 1/3 to 1/2 that max possible number, on average. but you should really still fuse for that number you came up with, because you can draw that much, and are safe up to that point.

 

[av83 10+ year member]

^^this. You don't always fuse for the wire. some amps are rated below the wire rating, the first thing in line to blow will be the amp, not the fuse. if your amp is rated over 300, then yeah, fuse your 1/0 for 300.

Fuse for the wire's capacity directly after the battery +. Fuse for the amp's rating right before the + terminal on it.

Edit: and if your amp is drawing more than three hundred amps, you better have two runs and dual inputs.

 

[dumpbeast86 10+ year member]

Fuse for the wire's capacity directly after the battery +. Fuse for the amp's rating right before the + terminal on it.

yes, that's acceptable for sure

that's why they make many different sizes

 

[av83 10+ year member]

yes, that's acceptable for sure
that's why they make many different sizes

That's the ”proper” way to do it. And is the only way I would ever recommend a ”noob”. That way it can't get screwed up.

 

[Kingstroker 10+ year member]

refer to this: Recommended Power and Ground Cable Sizes & Speaker Wire Size and Length

 

[Xjeff 10+ year member]

Ok thanks ill save them for incase I blow one at some time //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif