tuffluck

iTrader: (4)

i just installed my alterstart 200a alternator. i don't THINK my lights are strobing/flickering anymore (trust me it was obvious before, now i'm scrutinizing it like an eagle and i thought i saw a couple of fluctuations for the 10+ minutes i watched, but probably all normal). so that's good it's out of the way, but...

i have about 2,000 watts RMS in my stereo setup. i turned the bass WAY up and sat at a stop light. granted it's still light outside, so i couldn't watch my headlights, just watching my voltometer, it seemed to idle just above 13, then when the bass would hit it went lower, then start ramping up, then the bass would hit again and it'd go back down...repeat, etc.

is that normal? i thought people with aftermarket alternators, especially high output (HO) alternators, when they had a lot of power in their system.

btw, the voltometer never got in the red, just did what i described above. what is a normal place for the voltometer to stay? any input welcome...

fleetmgr

Alternators don't put out full voltage/current at idle unless they are built especially to do this. An alternator that's touted as being high capacity only means that it will produce more voltage/current (voltage limited by the regulator)...and here's the important part...at rated pulley speed. You don't achieve that rated pulley speed while idling. So, yes you will see a slight drop with a heavy load it idle. What in means in real terms is that while idling, you aren't charging your battery with the stereo cranked, you're discharging it.

tuffluck

iTrader: (4)

well the amperage on this actual alternator was tested before i bought it. it does 133.6 @ 833 rpm.

still i mean with all those things on it can get down to the red or close to, but i don't see my lights flickering. should i increase my idle maybe? i'm just confused...doesn't seem like i should be having this problem. i mean my bass REALLY hits when i turn it up, so maybe it's just a lot of power and to keep the lights from dimming the new voltage regulator just regulates this way?

what do you think? anyone else?

fleetmgr

You still have to have it spinning fast enough to maintain voltage in the presence of the load. When you see dimming, there's only 2 choices...it's either not spinning fast enough to maintain voltage for the load presented, or the regulator has a problem. You can either reduce the load or increase the idle RPM so it can handle what you're asking of it.

In the short term, like at a stop light, it's just an annoyance because the lights get a little dimmer for the duration of the light. In your Dallas rush hour traffic, or if you get stuck behind an accident you might have other issues.

The flickering you had before was most likely caused by a bad diode in the regulator.

tuffluck

iTrader: (4)

okay, thanks for the explanation, that is helpful. so do you think there is something wrong with my HO alternator based on the information, or under a high load does it seem normal?

also, i talked to the company that made the alternator, and they said that low volts on the HO alternator mean high ampearage is being used, so if you are using a lot of power (radio, lights, ac, etc.) at idle, the volts get lower because the accessories require more ampereage.

98ZEMT

iTrader: (5)

I'm not a big stereo guru or anything but I think if you use a capacitor it will solve the problem of the voltage dropping when the bass hits. I'm no expert so maybe ask in the stereo section. But I think the capacitor, if I'm saying it right, stores electricity so you don't get a big drop when the bass hits. Just something to think about.

fleetmgr

A capacitor physically and electrically large enough to actually do what you're thinking would help, but it wouldn't fit under the hood. If you were picking up alternator whine over the sound system a small one might help.

fleetmgr

No, I think it's fine and working just as it was designed. You're just putting too much load (load = stereo, windows, lights etc.) on it (or spinning it too slow) for the existing conditions.