amp wiring, fuse size?

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=104536
Printed Date: May 15, 2025 at 5:43 AM

Topic: amp wiring, fuse size?

Posted By: fredo2121
Subject: amp wiring, fuse size?
Date Posted: May 06, 2008 at 11:37 PM

I am new to this site and have done some searching to my question and get different answers from my reading so here it goes:
I have a Zeus 5 channel amp and i am running it at 4ohms and have wired it with 8gauge wire but it melted the fuse, i think the shop used a 40amp fuse but not sure because the whole thing was melted and i don't want repeat. The amp is 4x55watts + 1x200watts RMS. What size should i use.

Replies:

Posted By: teenkertoy
Date Posted: May 07, 2008 at 1:37 AM

A 40 amp fuse would assume the amp is 88% efficient, which it isn't. Is it listed in your user manual, or printed on the amp where the fuse is held?

The 8 ga. wire might be a limiting factor, the fuse at the battery should be no larger than 100amps.

-Justin

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Malcom: "This is the captain. We have a...little problem with our engine sequence, so we may experience some slight turbulence and then...explode."
Jayne: "We're gonna explode? I don't wanna explode.

Posted By: fredo2121
Date Posted: May 07, 2008 at 8:54 AM

Im not to worried about the fuse on the amp side. the amp has 2-40 amp fuses installed, one for the four channels and one for the 200watt sub output. i am referring to the fuse next to the battery, i will probably go with a with a 80 or 100 amp. what are peoples feeling on the fuse breakers, the local shop installer was telling me that this is what everyone is using thses days since you can reset the breaker so if i go with one of these i want to be sure that it is the correct amperage because once i buy it i can just swap out a fuse i have to buy a whole new breaker at about 20 bucks. opinions please...

Posted By: chillin420
Date Posted: May 07, 2008 at 1:57 PM

breakers are not worth the money. if they heat up to much they can weld shut so the "breaker" function will no longer work giving you no protection. stay with fuses. put a 80 amp fuse in the fuse holder by your battery and you will be fine.

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you can do it....
advanced MECP, lol does it really matter....
patience is a virtue

Posted By: jmelton86
Date Posted: May 07, 2008 at 5:27 PM

chillin420 wrote:

breakers are not worth the money. if they heat up to much they can weld shut so the "breaker" function will no longer work giving you no protection. stay with fuses. put a 80 amp fuse in the fuse holder by your battery and you will be fine.

/\ x2

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2013 Kia Rio -90a alternator
DDX470HD GTO14001 GTO1014D (x3)
Big3 in 1/0G
1/0G to GTO14001

Posted By: fredo2121
Date Posted: May 07, 2008 at 6:26 PM

thanks i think i will go with the 80amp fuse..

Posted By: teenkertoy
Date Posted: May 08, 2008 at 2:41 AM

Your breakers are heating and welding themselves shut? I'd love to see that posted_image

. Resettable circuit breakers use heat as a mechanism to break the circuit, usually by allowing a temperature sensitive metal to deflect far enough to trip the circuit. The only reason I could see one fusing itself closed is from a terrible design flaw. If however there is a secret world of breakers that work opposite to common sense, it's news to me.

If you want to choose a resettable one that works posted_image

, try the ones we have installed on our broadcast vans. They are the Klixon line from Texas Instruments and come in capacities of 90amps and 150amps and more, for 8ga. and 4ga. wire respectively. They don't cost much more than a fuse and holder. And no, these do not weld themselves closed. That I can personally confirm from experience using many different of these little guys, they work as intended.

-Justin

-------------
Malcom: "This is the captain. We have a...little problem with our engine sequence, so we may experience some slight turbulence and then...explode."
Jayne: "We're gonna explode? I don't wanna explode.