Increasing your alternator voltage output.

teamlseep13 · Post by **teamlseep13** » Sat Mar 08, 2008 2:02 am

If you look at the internal regulator switch that feeds B+ to the field coil you will see the square wave AC voltage sense line that tells the regulator that the field coil needs to be turned on. The voltage regulator operates that switch at 400Hz and PWM controls field coil current to regulator voltage.

The way the regulator is built, it is going to be really hard to get a diode into the alternator and have it all fit but never hurts to try.

Also, you will set a battery light if you charge much more above 14.6 I think. Not that it matters, just the PCM will freak and turn on the light.

I bet your amp has an internal voltage regulator so you don't get much more voltage than 14 into it, to protect the circuits.

p8ntman442 · Post by **p8ntman442** » Sat Mar 08, 2008 10:45 am

the amp internally regulates to pr0bably 12v. The higher voltage is going to just heat up the voltage regulator more. Thats how they work, they discharge the extra energy by heat. his lights however will still dim, they will just be brighter then dim to a normal level. I really have to suggest again, getting a spare, and bench testing b4 and after. The intent of this mod is not to supply more current, which is what his problem is,

slow'n'steady · Post by **slow'n'steady** » Sat Mar 08, 2008 4:26 pm

Amps can run up to 18V with a little modification. From the factory the one i have will make close to 10K watts at 17.7V

It was bench tested at 14.4V and put out about 5000W rms

p8ntman442 · Post by **p8ntman442** » Sun Mar 09, 2008 9:51 am

slow'n'steady wrote:Amps can run up to 18V with a little modification. From the factory the one i have will make close to 10K watts at 17.7V

It was bench tested at 14.4V and put out about 5000W rms

by a little modification you mean swapping out the mosfet and adding a heat sink.

Dont forget that upping the voltage will also affect the ecm. Im sure the voltage reg. in the ecm can handle it though.

teamlseep13 · Post by **teamlseep13** » Mon Mar 10, 2008 11:17 am

p8ntman442 wrote:the amp internally regulates to pr0bably 12v. The higher voltage is going to just heat up the voltage regulator more. Thats how they work, they discharge the extra energy by heat. his lights however will still dim, they will just be brighter then dim to a normal level. I really have to suggest again, getting a spare, and bench testing b4 and after. The intent of this mod is not to supply more current, which is what his problem is,

That is not how they work.

When the charging voltage goes above the set limit, there is a zener diode that is reverse biased before a transistor that turns the field windings on or off.
The zener diode allows current to flow when the set amount of breakdown voltage occurs, typically around 14V and this turns on a transistor that turns off the field windings. Then the charging voltage starts to drop off, the zener diode doesn't have enough bias voltage to allow current to flow, which in turn turns off this transistor, turning the field windings back on and building charging voltage up again.

More current, find a Seville alternator that is a 200 Amp and water cooled!

If more voltage helps out the amps(which I don't know much about) then try this out.

slow'n'steady · Post by **slow'n'steady** » Mon Mar 10, 2008 11:39 am

teamlseep13 wrote:More current, find a Seville alternator that is a 200 Amp and water cooled!

RLY? never seen/heard of that... What years did they come on? I was going to just buy a stocker for $20 on ebay then take it to a local shop and have them build it into a 200+ amp but i would like to see how cheap i could get one of those...

EDIT: found a couple... Gotta figure out if it is a "bolt on" for my eldorado and if so, I'm gonna snag one up and have it built. All i can find is a 138A version, no 200A...

The Dark Side of Will · Mon Mar 10, 2008 12:35 pm

The alternators used in cars with heated windshields had 3 phase AC taps for the windshield heater. I wonder if this is ALSO the water cooled alternator that I keep hearing about and they actually did need water cooling for the extra output...

teamlseep13 · Post by **teamlseep13** » Mon Mar 10, 2008 2:55 pm

2000 Deville has a 150A alternator. It has a liquid cooled rectifier bridge.
Model number LR-630.

The water cooling circuit def. works cause I have never had one fail on me.

slow'n'steady · Post by **slow'n'steady** » Mon Mar 10, 2008 2:57 pm

I found a decent priced high output (300A) alt so i am just going to get that and do this little trick and see what happens...

Thanks for the help...

lucky · Post by **lucky** » Tue Mar 11, 2008 3:59 am

instead of buying something bigger than a 5 farad cap u should get the reactor powercell battery
its a three post 16 volt car/truck battery with an external "switching" solenoid
wire your amps to that mo fo and use the cap for just your subs ans you'll be golden :thumbleft: