amp blowing fuses

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cycloneb18c3

Senior Member
ok, this isnt in a honda, but same thing as if it were!
I have a phoenix gold R5.0:1 amp(basically a 500 X 1)
I have the main power wire comming in (4ga) and it goes to a rockford fosgate 1 farad capacitor. it then splits off into 2 wires out(both 4ga), one for the phoenix gold amp(running subs) and a rockford fosgate amp(running highs). I have 2 JL W0's rated at 4 ohms. I wired these in parallel to get 2ohms. It is a 2 ohm stable amp. Main power wire is fused, with the fuse that came with the kit(i belive 60A fuse) the main powerwire fuse has NOT blown at all.)
now, the other day the phoenix gold amp stoped working. checked the fuses ON the AMP itself,(two 20A blade fuses) both of which were blown. I replaced them today, with another set of 20's and listened to the stereo at about 1/2 volume, and 1 minute later, pop, no bass, both fuses blown. I checked all the connections, and wires, and there cant be any shorts in the power wire. I also checked that the gain(bass) wasnt up too high, and it wasnt, because W0's are rated at 125 watts for optium power, so I had it set a lil less than half. after I made sure it was all good, I tried another 2 fuses, and 1 minute later of listening, pop, 2 fuses blown.
the rockford amp has worked perfect the entire time.
Help me! I got the amp as a gift for X-mas of 04, and I installed it in Jan. 05, so it isnt that old. My brother got it for me and he doesnt have a reciept(no warranty coverage!! damn him!)
what do u guys think?
 
ive heard of some amps coming from the factory with the wrong fuses in them, try running two lower fuses.
and make sure your ground is secure, if for some reason its scraping any metal and making a spark then it could be blowing a fuse. for that fact make sure you dont have any exposed wires.
 
yea, Im positive that there isnt any wires exposed, I checked them all yesterday. As far as running lower amp fuses, I shouldnt even try, because if its got enough of a short to fry 20A fuses, its got enough to fry 15, 10, 7.5, or 5's.
oh and the ground is good, its bolted right to the body of the truck, with a stainless steel bolt and a nylon lock nut.
 
you sure your speakers are wired correctly?
i would check the wires inside the box...
 
First mistake:
if you're running one 1F cap, going from one 12V 4ga in, to two 4ga out of the same terminal that is only made for one, is retarded. Either get a second cap, or run you Phoenix off the cap for your subs, your RF from your battery, and get a proper three terminal battery splitter (RF makes a good one). It sits on the power terminal of your battery, and you have room to properly fit your 1)power for the car 2)Capacitor 3)RF amp.
Battery Terminals RF

If you grab one of these, unhook everything, drain your cap, then repower it and remember:
1 12V + 1 Cap + 1 Amp + good connections = no blown fuses.

Your amps aren't getting the proper load from the cap being run in a dual configuration like that. Check the manufacturers specs for which fuses are to be used in your specific amps. Once you get your wiring redone and checked, you can usually run a fuse that is 20amps or so more than spec if you want.

Check your grounds (I hope your not running any less than 4ga). Sand off the connection spot well so there is no paint getting in the way. Your grounds are your most important connection.

When you're done with wiring, either get a volt meter, or if your cap is digital, make sure the amp you're running off the cap is getting around the 14.4V mark consistant. Crank your subs and if it dips down to any less than 12V, check your connections again and have a look at your alternator.

Let me know how it goes.
 
Originally posted by cycloneb18c3@Apr 8 2005, 11:01 AM
yea, Im positive that there isnt any wires exposed, I checked them all yesterday. As far as running lower amp fuses, I shouldnt even try, because if its got enough of a short to fry 20A fuses, its got enough to fry 15, 10, 7.5, or 5's.
oh and the ground is good, its bolted right to the body of the truck, with a stainless steel bolt and a nylon lock nut.
[post=484650]Quoted post[/post]​



if your running too high of a fuse it will blow.
my fuse in for my radio kept blowing and i could never figure out what it was. it turned out to be because i kept putting in 30 amp fuses when it was supposed to take 15 amp fuses.
 
Originally posted by micah+Apr 8 2005, 12:32 PM-->
cycloneb18c3
@Apr 8 2005, 11:01 AM
yea, Im positive that there isnt any wires exposed, I checked them all yesterday.  As far as running lower amp fuses, I shouldnt even try, because if its got enough of a short to fry 20A fuses, its got enough to fry 15, 10, 7.5, or 5's.
oh and the ground is good, its bolted right to the body of the truck, with a stainless steel bolt and a nylon lock nut.
[post=484650]Quoted post[/post]​



if your running too high of a fuse it will blow.
my fuse in for my radio kept blowing and i could never figure out what it was. it turned out to be because i kept putting in 30 amp fuses when it was supposed to take 15 amp fuses.
[post=484715]Quoted post[/post]​


True....But you have to do it within reason. You were running a fuse that was two-times the size of what you needed. You would be fine with a 20amp. You just dont want to bottleneck the system. Majority of the amps I've had came with a 50-90amp fuse. They come from the factory with those ratings to keep the amp safe of shorting out for the novice user ( a novice will usually have a basic wiring system and crank the gains). If you know your wiring and set up a cood cap setup, you can replace the fuse with a larger one and give the amp more power, therefore producing more sound. But as I said, I wouldnt reccomend just anyone doing that.
 
I ran 3 4ga off a caps before and never had a problem. A good rule of thumb is 500watts to 1 FA cap. It always worked well for me. My power line was 4ga as well. How long is your ground wire? If that is all set I would think about getting the amp looked at. Maybe there is something wrong inside the amp.
 
very could be an interal issue with the amp, but that would just suck...

bring it to best buy and have them install something, then complain that your amp keeps popping fuses after they worked on it :)


i haven't had a cap yet, just run 0 gauge...
 
LoL 0 is way more annoying to work with than 4 guage, and there is no need at his power level.
 
On a second thought, do this:
Take off your cap completely. Run the amp thats blowing fuses just off of your battery for a few days. If your fuse blows again, you know it's your amp. If not, it's your cap. Also, you said you're running two amps off the one cap? With 4ga wires? Well, considering a standard cap's terminals are only meant for 4ga wiring, how exactly have you connected 2 4ga wires to the terminal? Did you just try and twist them and jam them into the terminal? If so, reconsider. If your connections to the post inside the + terminal on the cap aren't rock solid, you do run the risk of a subtle short on the line, which would probably blow a fuse.

Instead of running 4ga from your cap to your amps, run 8ga. You wont loose any current.
 
yeah if you just twisted and jammed then in then the vibrations from the sub might be causing the wires to rub/spark/short

i wouldnt run multiple amps off 1 cap, but thats just me :p

then again i dont run caps, its like putting bandaids on a cut that needs stitches ;)
 
hey, well my cap has like an allen head bolt that goes into the cap, and the wires that hookup have eyelets on them, so they just get bolted on(its not like wires jammed into it) I can try hooking it up directly, but uh, I wont have any highs, and that wouldnt make sense anyway, because the High amp still works perfect. I donno, Ill give it a try anyway!

the ground wire is prolly like 15 inches long(if that)
 
good rule of thumb to try and keep your ground wire under a foot long, but i dont think thats your problem.
and if your sure you have them wired to the right ohm load then i have no idea what the problem could be.

try and turn down your gain.
if its 500 X 1 and wired at 2 ohms then your gain should be set at right around 31 volts.
multiply power times resistance and take the square root.
set your crossovers and eq's the way you listen to it, then turn your deck volume to as high as youd ever listen to it.
make sure you have a sine wave hz tone to set your amp with. you can get one from treo's website. then use a dmm to set your gain around 31 volts. this will keep your amp from -ever- going into clipping range.

sine waves run at much higher voltage then normal music so generally speaking you can bump up the gain a tad after setting it this way, but if you do set it this way it will garuantee that you never run your amp to clipping.

clipping is when the music signal starts to square off, its bad for your subs/amp and can cause problems ;) if you have an osciliscope you can set it with that also.


http://www.teamtreo.com/view.php?showme=Free_Test_Tones

link to some sine wave hz tones, use a 50hz to set your sub amp
 
i still vote for checking your internal wiring in the box...

and i agree with above to recheck your ohm load...

other than that... listen to the man above... he seems to know his shit...
 
if none of that helps try posting your question here

http://forums.caraudio.com/vb/index.php

forums bigger then hondaswap dedicated to car audio.

or research here

http://www.bcae1.com/

site that has an unmeasureable amount of knowledge for car audio. alot of it is typed in "genious" but once you get to the normal every day kinda guy language you can learn alot.
 
Ok this kinda goes along with what they were saying about rechecking your ohm load. You said the name of the amp and all that but I am unfamiliar with it so.... If it is a true 500x1, meaning it is a monoblock amp and can only take in 1 positive and 1 negative then the following doesn't apply. However if it isn't a true monoblock then I was thinking maybe you bridged the amp. This means that you took the 4ohm subs, paralleled (however u spell it) and dropped them to two ohms, then bridged the amp which would cause the ohm load to drop in 1/2 making your amp run at 1 ohm. Just an idea, I;ve seen lots of people do this on accident w/o thinking. Hell the first time I hooked up 4 twelves I had them running at a 1/2 ohm on accident and the amps just kept shutting off. I would also get rid of that cap. Like someone said, it's like putting a band-aid on when you need stitches. There is no point, imho, in getting a cap if you haven't first replaced ALL of your ground wires with the same gauge as your power wire and/or upgraded your alternator. Hope ya get it figured out.
 
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