Alternator Ripple?

[yacob.naif 10+ year member]

Well, i've been doing lots of searching trying to figure out how big an alternator i need to properly power my system, since i'm forced to buy a new one anyway after breaking my factory unit yesterday.

And i figured out that the crazy wobbly signal i got while trying to set the gains on my hifonics bxi2006d with my o-scope was actually alternator ripple.

It really doesn't matter much at this point, since it's getting replaced anyways, but was this a simptom of a dying alternator, that wasn't switching fast enough to eliminate most of the ripple anymore? Or was this caused by grossly underpowering my amplifier, where the amp was drawing directly from the alternator, since the alternator wasn't charging my battery fast enough to supply it with conditioned power?

Or both?

Like i said, it doesn't really matter, i'm gonna order a new alternator tomorrow anyway, but i'm just curious what the problem was.

I didn't know there was a name for it, i just thought the amp was underpowered, and couldn't form the waves correctly, so i just backed the gains down until the waves looked normal, and called it a day. I was probably only getting around 800w out of my amp.

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[helotaxi 5,000+ posts]

Could have been a sign of a bad battery or a bad alt or insufficient capacitance in the power supply of the amp. The capacitor bank in an amp is there to filter out voltage ripple.

 

[yacob.naif 10+ year member]

Ok, that makes sense.

I'm completely rewiring the system with 1/0 and 4 gauge wire, it was originally wired with 4 gauge mainline, and 8 gauge going to my amps..... Ya, i know.....

I'm guessing the 8 gauge could've had a lot to do with insufficient capacitance in the power supply of the amplifier itself, but i don't think a new alt will hurt either //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif Especially when i can get my dad to go 50/50 because i've still got a raincheck for a birthday present and a christmas present.

Merry christmas, car.

If i'm still seeing ripple, i'll suspect the amp. By replacing so much (all) of my installation equipment at once, i'll never really know what caused the ripple in the first place, but i'll be happy enough if it just goes away. Overrating of hifonics amps is pretty much a non-issue when i can't even get 1000w out of it before my power supply starts shaking at the knees.

Thanks for the info.