Fuse size

I have two amps in my car and I blew the main fuse today. It was a 60amp fuse. It blew during normal driving and listening to the radio. I decided to get a bigger fuse 80amps and I blew this fuse after four minutes of playing music. I have a 1100w amp @ 1ohm pushing my 2 10w6v2's.
I also have another amp for my highs 4x90w @4ohms. What fuse size should I use for the main fuse coming off the battery?

Assuming a 12 volt charging system, your 1100 watt amp draws about 90 amps of current, while your 4 x 90 draws about 30 amps. Each should have their own fuse located in a distribution block, but your main fuse should big enough to cover both of them. Always round down. (i.e. if you draw 120 amps, but can only get a 100 or a 150 amp fuse, go with the 100) a circuit breaker is a good alternative for a main fuse, but only if you have a separate dist. block with propervalue fuses protecting each amp in the system.

I'm long winded. you need about 120 amps of fusing.

Hope that helps!

-------------
~Cory
Car Concepts SLC
Alpine F#1Status Certified

You should be checking your system over completely if you blew 2 fuses in 1 day, , they may be a problem.    Putting in a larger fuse after thr first one blew was very risk taking.   When a fuse blows, you should put one in that is half the rating and listen to your system at a low level to be shure everything is fine.  If that fuse blows easy, then you go a prob.    Definately check all your connections, and grounds before you put a bigger fuse in.  Re do your grounds if you care about your system.

Thanks for the advice. I checked over all the wiring and reconnected each ground wire. I put in a 50amp fuse to test everyting at low volumes. Everything sounds fine. So I think I just need a bigger fuse. I just recently added the 1100w amp for the subs. It ran fine before that on the 60amp fuse, so I think I'm going to try a 100amp fuse. Once again, Thanks.

I would seriously recommend that you actually read the supplied documents that came with the amplifiers.

Then add up the total current draw it states for both. At that time, you will be informed. Then you may install the appropiate rated fuse, to protect you, the vehicle, and any components which you deem important.

The ghetto way, is simply adding up the fused rating on each amplifier.

Regards

EVIL Teken . . .

Thanks for the info The 1100w amp is rated for a 90amp fuse and the 4x90w amp is rated for two 30amp fuses. So would a 150amp fuse be what I need?

Don't put a bigger fuse on it. Find out the current draw and fuse accordingly.

-------------
~The Rookie~
Rookie of the year that is...
Don't let the smoke out of your equiptment..it doesn't go back in.

Where do I get the current draw information from?

Teamrf wrote:

---

Don't put a bigger fuse on it. Find out the current draw and fuse accordingly.

---

Exactly. Mathmatically, 150 is right, but see if the owner's manual has a listing based on your system configuration, or a good multimeter can help you determine actual current draw. My previous post is based solely on the mathmatics for the equipment you posted, so it is just a reference, a guideline to help you know when you are close with your more accurate calculations.  Always err on the side of caution, however.

-------------
~Cory
Car Concepts SLC
Alpine F#1Status Certified

Teken is bang on with what he posted. In most cases you will not be drawing the rated value of the fuses in the amps, nor can most batteries / alternators give you this much current while maintaining operation of the vehicle and it's accessories as well. The purpose of this main breaker is to protect the vehicle from short circuits in the power line between the battery and the amplifiers / rear batteries / capacitors. Should your value be too small, then yes if you do play it at a loud volume level, the current draw may exceed the rating of the fuse. A 150 amp resettable breaker is a good bet.

There is usually no need to fuse amps at the rear of the vehicle anymore as most amps now have built in fuses to protect them. Fused distribution blocks were primarily designed for amps that had no fuses in them, like old Rockford, Linear Power, Orion, PPI, Alpine etc. If you have a cap or battery in the back of the vehicle then it is a good idea to have a breaker in the back of the vehicle as well, between the cap / battery in the back and the main breaker up front. Current flows in both directions, most people do not adequately protect their investment.

-------------
Top Secret, I can tell you but then my wife will kill me.