Capacitor Question

[rodney]

the caps with the voltage monitor built on, is it reading the voltage of the cap, or the voltage of the battery?

[sound_xtreme]

the cap

I could be wrong here, but I think they measure the voltage of your whole electrical system, and the cap would have the same voltage as the rest of your car. If what I learned in electronics serves correctly, the voltage will always stay the same, it's the amperage that would fluctuate.

^^^ yup ur wrong

how would it carry a different voltage then what the car is feeding it?

[sound_xtreme]

very wrong. caps measure the inside voltage of the capacitor. thats what a capacitor does stores voltage and can store voltage higher than the rest of the system. lets say ya got a 24volt cap, and its readin 24 volts, you tellin my your batts and alt are all running at 24 volts? dint think so

that's interesting.... didn't know that's how it worked

[alero_ecotec]

A capacitor can hold different voltage b/c of how a capacitor works. Taking physics in highschool and being an electronics freak u just know stuff like this. A capacitor holds ecectricity and dumps it all at one time when your Amp needs it. That way it can charge while there is a break in the bass, keeping lights from dimming, or the battery from running down. The current in the electricity stays the same, but you can build up voltage in the capacitor. Depending on the size of your system i would definately go with a 24V capacitor, with a cap, just so you know everything is working good and what not. Also, its always recommeded that u should have about 1 Farad for every 1000 watts your going to be pulling. Capacitors are measured in Farads, the more farads, the more juice your capacitor is going to be able to hold. And you always want to install your capacitor with the shortest ground wires you can possibly use, so ground it at the nearest point you can.

[sound_xtreme]

also discharge rates are something to look into.

very cool, thanks for the info. I've read a little into capacitance, but haven't TOTALLY understood it. Speaking of discharge though... it reminds me when I used to work in a photo lab... we used to take those disposable cameras after the film was taken out, and charge the cap for the flash and shock each other... stupid but funny

that is actually a good question...

my cap has a voltage meter, and during some diagnosis i was doing, it followed my battery voltage verrry closely.

so, it does measure the voltage across your cap, but in most cases i have seen, with a 12v cap. it should be the same.

ps, im an electrical engineer, i should know this.. but i dont! better hope i never design the computer for your car in 5 years!! lol

[xsavyor1]

the volt meter on th cap is reading the voliage that flows acrosed it. so it will read the volt. of the battery. a cap charges and unloads so fast it would not read just the vot. of thecap

i think we are using two different terms to talk about the same thing..

Voltage ACROSS the cap and voltage OF the cap are two different things.

one end of your cap should be tied directly to your battery, the other end groudned.

so unless ur have a crappy ground, the voltage across the cap, should be the same as the battery....? maybe?