Print Page | Close Window

total system fuses

Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=102549
Printed Date: May 11, 2024 at 5:53 PM


Topic: total system fuses

Posted By: tezjet
Subject: total system fuses
Date Posted: February 25, 2008 at 4:08 PM

Soo I was wondering if this is restricting my system or how it is even possible.

My 73 Duster is currently setup with 4awg running about 10 inches off the battery with a inline agu 60 amp fuse. It then makes its way to the trunk with about 12 feet of the same 4awg cable. It meets up with a distro block where it turns into about 1 foot of 8awg and runs into a BXI1606d Hifonics amp which has 2 70 amp fuses. The amp is wired into a ported 35hz custom built box with speakers wired at 1.5 ohms with (2) cheap dvc 6ohm subs. There is also a 8 guage running under the backseat about 4 feet into a 100x2 amp running about 200 rms. WHY has the fuse not blown under the hood? It is my understanding that a 60 amp fuse should not be able to handle 1000 real rms that my system should be placing out.

My calculations:
1.5 ohms Hifonics says it puts out 1300ish but I know that is overrated so I am counting it at 900ish.
100x2 running one channel 8 ohms to two speakers so around (25+25)50 rms and other channel running at 2 ohms to two 6x9 giving them (70+70)140 rms total.

I have not done the big 3 yet but I can tell my alternater is getting taxed pretty hard. The battery will prolly be going soon as it is about 2 years old and a costco cheapy battery.

Where could my system be restricted? Why hasn't it blow the inline or distribution blocks 60 amp fuse? I have a 2awg Fosgate wiring kit I will be putting in soon, but really am just wondering about those 2 questions to tell if I really need it.

Thanks for any insight or help.
~Steve



Replies:

Posted By: haemphyst
Date Posted: February 25, 2008 at 4:19 PM
Because you aren't pulling that much on a CONTINUOUS basis. Operative word...

A 60A fuse can sustain 120A for a relatively short period of time, befire it blows.

BTW, your underhood fuse should be a 150A fuse.

-------------
It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."




Posted By: Alpine Guy
Date Posted: February 25, 2008 at 4:22 PM
You should like stated above have a 150 amp fuse for your main 4 awg, then for your Hifonics amp you should be running 4 awg also fused at 150 amps to properly supply your sub amp, your speaker amp can be fused up to 60 amps since thats what the 8 awg can handle up to.

-------------
2003 Chevy Avalanche,Eclipse CD7000,Morel Elate 5,Adire Extremis,Alpine PDX-4.150, 15" TC-3000, 2 Alpine PDX-1.1000, 470Amp HO Alt.




Posted By: KPierson
Date Posted: February 25, 2008 at 4:39 PM

Why would you guys recomend a bigger fuse?

If he is running the system now without blowing a 60A fuse why put in a 150A?  The 60A fuse isn't negatively effecting anything.



-------------
Kevin Pierson




Posted By: tezjet
Date Posted: February 25, 2008 at 4:41 PM
hmmm, I just recently got the Hifonics amp thus why my fusing was all screwed up.

Do you see any reason for me to install my fosgate 2awg wiring over the 4awg with the current system specs? Do you foresee any power problems with the 4awg? The 4awg kit was part of a cheap flea market setup if that matters at all. Last question, if I add in a set of components for the front running off a amp pushing 125 rms a side, will the 4awg be capped or still okay?

Thanks for the info and look forward to any more.
~Steve





Print Page | Close Window