QuestionQUESTION: The fuse from my amp to my battery keeps blowing. When i replace the fuse one of 2 things happens. 1) The power cap starts of with a reading of 15.3 or so and then when the power cap goes off the fuse blows OR 2) The Power Cap shows 15 or so, then shuts of and the fuse doesn't blow until i start my car (which I don't even have to fully start the car, it will blow if I just put the key in and turn it on). I did check and see that the fuses for my amp are not blown, they are still good. It might also help to know that this started a few days ago. I was driving and I went to swat something by my leg and hit the knob for my remote to my amp and it went all the way to max and then I lost sound. I can still hear through the stock speakers though. I paid someone to put the Amp and Power Cap in for my car and I don't know tooo much about car systems, but if you can explain anything I will be able to figure it out. Thank you for any help in this matter.
ANSWER: A power cap is merely a large capacitor, usually 1 or 2 FARADS. I holds a very big charge and its primary purpose is to hold up the voltage to your amp during low frequency passages of audio.
There should be a charging resistor in series with the cap; if not, the current rush for first charging up the cap will be so great the fuse will blow every time. So, you must check the series resistor between the cap and battery or 12v. My suspicion is that resistor is defective in some way or shorted out. So, look at it or replace it and see if that does not solve the problem.
C
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QUESTION: Sorry, but my knowledge on systems is not good at all. What exactly am I looking for as far as a charging resistor. Can you give me an example of what one would look like? Do you mean the case that covers the fuse? I know there is a red wire that goes from the cap and connects to a case which holds the resistor and the other end of the fuse connects to another red cable which connects to the battery.
ANSWER: When the capacitor is fully discharged it acts like a short during the first few milliseconds until the charge starts building up.
If the capacitor got discharged, somehow, it will blow the fuse every time that battery voltage is applied. The charging current with no resistor in series will be like a dead short to the battery for the first few milliseconds.
Here is a procedure on how to do it without a series resistor. It is maybe a better solution for you if the original installation was done without it.
http://www.caraudiohelp.com/car_audio_capacitor_installation/car_audio_capacitor
Please study the above site and charge up the capacitor as shown. If it does not hold a charge for very long it means there is some kind of shorted condition.
So, if it is losing its charge, disconnect it from the amp temporarily and charge it up again with no connections; then you will learn if the cap has been shorted internally.
The color of the wires do not mean anything; the power cap booster can be wired in with any color. But, you must know where the wires are going in order to understand the charging and discharging pathways.
The charging cycle explained in the web page above is very important to follow.
Hope this clears it up.
C
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QUESTION: I did, this and everything was good. When just the capacitor is connected (amp ground and chassis ground hooked up to the capacitor and the positive to the battery hooked up) and the vehicle is running I get a reading of 14.67, but once you plug the amp power cable to the capacitor it blows the end line fuse from the battery. Fuses in the amp are ok.
AnswerI am guessing either you have the polarity reversed on the cap or you have it miswired somehow.
You might try disconnecting the power cap and just operating the amp without it. Then, if that is okey, touch the charged cap to the amp 12v line and see if that works.....
Good Luck,
C
