quattro digest, Vol 1 #4458 - Voltage Question

[Larry C Leung]

Not knowing the rest of your current load on your car, I'd
say you are WAY under-amped. I'd suggest at minimum,
120A and I wonder if you probably need more. A drop
to 12V assuming all else is okay indicates that the
altenator is unable to keep up with your load. It can
only keep the voltage at 14V if it can flow enough current.

The analogy would be to think of water pipes as your wires,
current as the Gallons Per Minute through the pipes, and
voltage as pressure. If you are asked to flow more water
than the pump (altenator) can supply, than the pressure
can't be maintained.

HTH,

LL - NY


> From: "passat TS" <passat_ts at hotmail.com>
> To: quattro at audifans.com
> Subject: Voltage Questions???
> Date: Mon, 13 Jan 2003 15:25:03 +0000
>
> [ Converted text/html to text/plain ]
> I installed a new pair of big Hella 4000's in my rally car (you can
> see it at
> http://forums.audiworld.com/other/msgs/732643.phtml[1] )
>
> I calculated that I'm using around 55-60 amps with everythingthat
> draws on.
> The alternator is a stock one, i.e., 90 amps.
>
> The questions are:
>
> When I turn the auxiliary lights on (400 watts total), the
> voltimeter gets
> down from almost 14V to a little over 12V. Is this OK?
>
> Should I think about upgrading my 90 amp?
>
> TIA,
>
> Carlos.