can you clarify this for me? i dont know how it would be capable of doing this if the amp is over powering the alternator, playing at that rate. i dont think it would be capable of maintaining 14v? does that make sense? enlighten me pleaseeee
Thinking about it more, I think I put my foot in my mouth. I myself am not completely understanding why the alt is not supplying 14V at idle, system on or off.
It's 3:30am here, so bear with me, as I might be completely wrong and out of my mind until someone else agrees with me.
When you're amp sends out 2000wrms to the subs, it pulls the power from your batteries (assuming you have 2), so your alt doesn't necessarily "take the hit" as much as your batteries do. Obviously your alt cannot provide the 150+ amps of juice required to produce 2000W, it's all coming from the batteries. The 80A figure is how much power the alt is charging you're battery with.
Engine off, the battery should be at 12V or higher. Engine on, the battery should be at ~14.4V, because that's the voltage the alt outputs, as far as I know. One would think the alt should run at 14.4V to supply the same 2000W of power with less current [where Power (W) = Voltage (V) x Current (I or Amps)], thus letting the alt not have to work as hard to keep up with the system's draw on you're battery.
As far as I know, a healthy alt puts out 14V+ and a dying alt will drop below 12.5V, but let me double check that.
Voltage should never be above, say 14.8V, otherwise you risk frying circuitry and electronics that were designed to run on a 12V system (as opposed to 120V and 240V residential wiring, or 360V/3P industrial wiring)
EDIT: Some quotes from old farts on HAF I consider more knowledgeable than myself:
Another thing to check is system voltage when it's running. Measuring parasitic current when the car's parked doesn't really say anything about the capacity of the alternator.
The one time when the alternator SHOULD have the most difficulty keeping up with demand, is idling with all possible loads turned on. You could even check this with a cheap voltmeter, here's your test...
Go for a drive so it's warmed up, let it idle with everything turned off.
Measure system voltage, easiest place is at battery posts. Should be 13v to 13.5v depending on the accuracy of your meter.
Now turn on everything you can find. Headlights, stereo, rearwindow defogger, ventilation blower, jumper your fan switch so the radiator fans run, whatever else you can imagine.
How much does the voltage decrease with all that stuff turned on? When you compare loaded & unloaded using the same meter, you sorta work around the issue of the meter's accuracy. That's the test for whether the alternator is putting out OK. If it can keep up at idle, it should be fine.
So I guess you're in the clear, considering how big the load you're drawing is.... interesting. Learn new stuff everyday.
