Real World voltage

[bkman4]

I just installed a HO alt, and an external regulator. They both perform great and I couldn't be happier. If anyone need this kind of set up, there is a guy on termpro that does this...like half the price of most audio elec. co's, contact me. So, my question is what is the safest voltage you can run a car at...the reg is adjustable all the way to 21v so I know I can't go that high, but right now I am at 14.9 with no probs. Does anyone have real world experience on how high you can run a daily driver!?!?!? Thanks in advance.

[bkman4]

ttt

common guys!

[PBCrunch]

Depends on the car. You don't want it too high or you will damage your amps. Alot of them have protection to keep them from running above ~15.5V.

[Shark]

Also depends on the vehicle...
wouldn't want to go start frying computers/electronics in a newer car.....

If it was me, I wouldn't go much higher then that......

[bkman4]

That is what I was thinking...I'm not to worried about the amps...more about the car, because I really don't want to fry any computers! :eek:

[Haunz]

A wise man once said..

"crank it up... f-cker.."

If I had some amp that could run off 17 volts (I will soon) then I would want to run it at 17 volts!!!

Probably the best aproach would be a 2nd. alternator with it's own battery... but that might be out of the question for a "daily driver"

I guess one of my first questions is weather or not there is a drop in the amperage the alt. can make running at a higher voltage???

But for your situation... with the car being your regular transportation... I would still crank it to 15.5-16 volts and see what happens...

But hey... I am reckless...

[Richard Clark]

bkman4-------the answer to your question is not a simple one-------the best charge voltage depends on the prevailing conditions-----they are many but here are the top two factors and they have nothing to do with the stereo-----the ambient temperature (batteries charge differently at different temps)-----your driving conditions (stop and go driving demands a higher charge point than long distance highway conditions)-----less important???????------life of other components like headlight and other bulbs (higher usually means shorter life)------life of auto electronics (most OEM parts have internal regulators if they are voltage sensitive so this is not usually a problem unless things get really high--------battery condition (a battery that is not up to snuff requires longer and higher rates to replentish)--------and last????-----performance of your stereo-------higher up to a point (usually about 16 volts)is usually better---------the real problem is that no single point regulator can be correct-------someday (with the advent of more advanced 42volt systems) the regulators will incorporate intilligent processor controlled charging profiles that can vary the set point depending on conditions----------so for now here is the best answer you can expect-------the best charge point is the LOWEST that you can set the voltage at and not notice a decrease in overall performance and reliability, and without ever having to worry about the car not starting--------thats how the OEM's determine it and its still the best..........RC

[bkman4]

Thanks for the insight Richard. As far as the dual, alt/batt setup, that is not out of the question, but it is not needed YET. I'm charging @ 14.9 right now, and even under extreme draw, my current never really goes below 12v. However it does drop a little, especially with a few accessories on and that can make my lights dim :mad: . Now, Richard, my question is what should I do, short of another alt or batt, to "stiffen" up my power supply. I know you said caps aren't totally useless, but they need to be paralleled to decrease the ESR, to be effective(correct me if i'm wrong). So, how many caps need to be paralled together to give a low enough ESR?? I have a 180 amp alt, and my stereo shouldn't draw more than 140 amps, even though the whole thing is fused through a 100amp breaker.

Edit: if you can parallel caps...can you series them???

[ June 24, 2002, 03:06 PM: Message edited by: bkman4 ]

[Shark]

You could series the caps, but it would be totally pointless.....
you'd have a higher ESR, & say putting a pair of 1 farad caps in series,
you'd end up with essentially a 0.5 farad cap.....

(capacitance is opposite of resistance)....
capacitance in series goes down...
resistance in series goes up....

[808BUFF]

You might want to look into getting a Harrison Lab Flux Cap that's rated to keep a constant voltage of 14.7 during a 100 amp draw, but it's expensive!

[bkman4]

Bass-Head...I can gather how to parallel caps...how would you wire them for series? :confused:

808: If I'm not mistaken the FluxCap is of the same concept as the Jacobs Accuvolt. They draw MORE current to make up for voltage. So my draw and voltage drop at the battery would actually be worse. :eek:

I'm trying to figure out how many and what size caps to use to lower the esr enough for it to be worthwhile using?!? graemlins/idea.gif

[bkman4]

ttt