Print Page | Close Window

Keep blowing 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=81139
Printed Date: April 19, 2024 at 4:40 PM


Topic: Keep blowing fuses

Posted By: Markland556
Subject: Keep blowing fuses
Date Posted: August 03, 2006 at 3:33 AM

Ok, well i keep blowing fuses now that i have my new JL 1000/1 and MTX 9500 in i blow fuses.
Ok, here is a basic pic of my setup. Just look at it, there is a cap there too but it doesnt matter with the way its setup.
So, #1 is a 60amp fuse, #2 120 fuse, #3 80amp.

Im almost certain that 80 just isnt enough. What should i put there. And the reason for #3 is because its easier to replace.
#1 and 2 are mini ANL and #3 is glass.

posted_image



Replies:

Posted By: djfearny2
Date Posted: August 03, 2006 at 7:27 AM
ok according to pic i dont get it.


ok one you dont say what guage wire. two there is no need to have two fused on the wire going to the sub amp. second the fuse levels are probably off.

off the battery should have a fuse (preferable less than 12"). like an 80 or 100 i dont know the amps being drawn so i dont know for sure

a distribution block off of the main wire as it seems you have.

the two fuses on the distribution block should be equal or less than the fuse comming from the battery. this will balance it out. also if you are blowing fuses off the sub amp you could be over working the amp, that amp has thermo protection and one thing it does is blow fuses for protection so. you might be exposing it to a very low ohm load or your ground is not sufficient. the actual fuses should not be blowing . there is a higher cause for it.

-------------
Jon
Installer/Help Technician
---coral springs florida---
mecp certification is not always needed. I have it and it has not helped me out at all. my experience out shines it.




Posted By: haemphyst
Date Posted: August 03, 2006 at 9:47 AM
The main power wire... What gauge is it? You need a fuse in that for protection of the car. If #4, it MUST have nothing larger than a 150A in it, as djfearny2 said, within 18 inches of the battery. You are looking at burning your car down.

The 1000/1 is GONNA blow 80A fuses, with EASE.

1000/.6=1666 watts in
1666/14.4=115A
1666/12=138A

You will want at least a 100A fuse in that fuse holder, probably a 120A would be better. With one amplifier pulling as much as 120A, a #4 power cable will be a bit undersized, you're going to want to have a #2 (fused at or below 225A) or even better, a 1/0 (fused at or below 350A).

Get rid of the fuseholder #3, and just use the fused distribution block.

-------------
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: Markland556
Date Posted: August 03, 2006 at 10:42 AM
Ok, sorry for not showing it. The wire is 0 guage to the distribution block. Then its 4ga. There is a 150 amp fuse within the fist 12" of the battery. The point of fuse 3 is that is easy to access. I was thinking of getting a circuit breaker there.

How would i know what the problem is. The amp has lights for low ohm, low volts and thermal and none of them come on. Im sure my ground is sufficient.




Posted By: haemphyst
Date Posted: August 03, 2006 at 11:06 AM
An 80A is too small... THAT'S what your problem is. As I said, you'll want at a minimum, a 100A fuse there. Your primary fuse should be bigger, at least a 200A, especially considering the current demands you are placing on that cable.

-------------
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: Markland556
Date Posted: August 03, 2006 at 11:18 AM
So for the fuse next to the battery go 200A amd change the fuse 2 like 120. And then ill just eliminate fuse 3.




Posted By: jstruckman
Date Posted: August 03, 2006 at 12:04 PM
yes

-------------





Posted By: cafociguy
Date Posted: August 03, 2006 at 12:57 PM

Markland556 wrote:

So for the fuse next to the battery go 200A amd change the fuse 2 like 120. And then ill just eliminate fuse 3.

Another idea you might think about is eliminating the fuses, a 200A fuse costs what like 10-15 dollars why not get a circuit breaker, never have to buy fuses again here's a link to a 100 amp circuit breaker made by stinger https://www.cardomain.com/item/STISCB100 , I am actually running one 135 amp for my 2 Xtant amps and I have never had it pop or anything, it's also alot easier if you have to run some different wires, or if you have to take your car into the shop you can just push the breaker release button and no one can turn on your system.  That's probobaly the best investment I have made in my system, the Stinger fuses I was going to run were going to be about 20 dollars for 3 and the circuit breaker is only about 35.  much better investment.  Hope that helps.





Posted By: jazzcustom131
Date Posted: August 03, 2006 at 1:13 PM

Haemphyst, im' confused. What's with the 1000/.6 calculation?? I understand the other things, as they come straight off the pie chart, but I must be missing something, cause I don't know why you did that



-------------
Greed is for amateurs.

Disorder,chaos,anarchy now THAT is fun!!




Posted By: haemphyst
Date Posted: August 03, 2006 at 4:05 PM
Efficiency should ALWAYS be figured into any current demand calculation... That's exactly what I did.

A 1000 watt amplifier, is 1000 watts OUT, divided by .6 (in the case of Class A/B, which I assumed the 1000/1 is) is 1600 watts IN. 600 watts blown off in the heatsink. In the case of Class D, I would generally assume 85%, so the numbers would be 1000 watts OUT / .85 = 1200 watts IN, only 200 watts blown off in the heatsink.

Read here a recent thread regarding those calculations.

-------------
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: jazzcustom131
Date Posted: August 03, 2006 at 5:44 PM
Read the thread, still have a question, but i'll pm you about it. It was highly informative though.

-------------
Greed is for amateurs.

Disorder,chaos,anarchy now THAT is fun!!





Print Page | Close Window