Battery Charging

[Grant Lenahan]

All true.

or a regulator that has a series failure ( high impedance)

Grant
On Feb 23, 2008, at 6:04 PM, Huw Powell wrote:

>
>
>> The alternator light doesn't tell you anything about the battery, it
>> tells you the alternator is not charging the battery.  If the
>> alternator is spinning and producing a current flow, the current that
>> creates the magnetic field in the rotor is generated by the
>> alternator.  If the alternator is not spinning, like when you start
>> the car, the current to create the magnetic field is supplied through
>> the alternator light.  The light switches off due to the magic of
>> diodes and equal voltage potentials,
>
>>
>> Any way of testing if the battery discharge light is really testing
>> if the battery is discharging? Battery discharge light on dash tests
>> voltage? Current?
>
> So what iut *really* tells you is if the alternator is functioning  
> properly.
>
> And if it's not... you are discharging your battery to run the car.
>
> If it's lit, two main culprits - worn, loose or broken alternator  
> belt,
> or worn brushes in the regulator assembly.
>
> Wiring/ground quality can also be an issue.
>
> You can always set up an external voltmeter attached to the cig  
> lighter
> or some such if you suspect charging/voltage issues are a problem.
>
> -- 
> Huw Powell
>
> http://www.humanspeakers.com/audi
>
> http://www.humanthoughts.org/
> _______________________________________________
> quattro mailing list
> quattro at audifans.com
> http://www.audifans.com/mailman/listinfo/quattro
> ---
> Watch this space for ads :)