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Subject:Re: Adjust Battery LED Pot
From:David Schwarze
Date:Mon, 28 Nov 94 10:17:24 PST

Harmon Seaver writes:
> 
> On Sat, 26 Nov 94 21:28:44 CST, DerekDrew@aol.com wrote:
> > 
> > You all know that 11.9 volts is a dead battery; 12.25 is half charged, and
> > 12.6 is fully charged, right? 
> 
>     No, that's not true. A battery in good shape, fully charged would 
> read about 13.5 volts, not 12.6. Any battery that only reads 12.6 after
> a good charging-up is ready for retirement. And anything reading only
> 12 or less is junk. In fact, I wouldn't dream of keeping any battery
> this time of year that read anything less than 13v after a charge.

Harmon,
	I think you will find that as soon as you attach a small load
to that battery, or leave it sit for a few hours, the voltage will drop
down to around 12.7.  I wasn't sure of this myself until I got a decent
digital multimeter.  The 13.5 reading that one gets briefly after charging
a battery is pretty meaningless.  I have had old batteries that read 13.5
after a charge, but dropped to 10.5 (or less) within a few minutes when they
were put under a 5 amp load (da fridge).

-David

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David Schwarze			'73 VW Safare Custom Camper (Da Boat)
SAIC Comsystems, San Diego	'73 Capri GT 2800 (Da Beast)
schwarze@nosc.mil		'87 Mustang Lx 5.0 (Da Bruiser?  Soon...)
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