Re: 12 volt power source?

On Sun, 23 Dec 2007 16:17:51 -0500, I said, "Pick a card, any card"
and Charles Davis <cad@xxxxxxxxxxxx> instead replied:

Ray Haddad wrote:
On Mon, 24 Dec 2007 07:59:52 +1300, I said, "Pick a card, any card"
and Greg Procter <procter@xxxxxxxxxx> instead replied:

I may well be an idiot, (I'm answering you afterall) but why is it the
"laboratory (style) power supplies" I can buy from electronics chains
like Dick Smith and Jaycar are 13.8 volts???

Because the circuits those things run on are powered by an
alternator running at 13.8 volts. The battery in most vehicles is
only for starting the vehicle

NOT!!!!!

Yes it is. It also provides stator winding current but never, ever
will the battery be a 13.8 volt device.

There is this little thing commonly referred to a 'Voltage Stabilization'

I.E. the "12 Volt Lead Acid Battery" serves as a 'low impedance load for
the electrical system' and also a 'medium impedence source for current
when the 'Alternator/ Generator' is not supplying power.

See the above, Chuck. I realized I left out that important use but
it is NOT for running all the accessories. When the alternator is
running, the automotive voltage regulator (not to be confused with a
real voltage regulator as used in electronics) isolates the battery
from accessories in the car.
--
Ray
.

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