Battery Condition Alert

I have a Reatta that, seemingly under the best of conditions, draws a fair
amount of resting current. Too darn many systems involved I guess.

I don't drive it that often, and yesterday after letting it sit for several
weeks, I found that the battery was flat.

It charged right back up and started like a champ, but I got to thinking
that
I could probably cobble up a voltage comparator that would constantly
measure the battery voltage, drawing almost no current. When the voltage
drops below some preset value, the comparator would activate and an
audible alarm would sound.

The percent of charge is related to the voltage at a constant temperature
by a simplified equation:

Vt = Vc + C

Where Vt is the voltage measured at the terminals
Vc is the voltage at which the battery is considered to be totally
discharged at the
same temperature
and C is the percentage of charge, expressed as a fraction.

Sorry, this message was not intended to be posted.

Found this smart switch that could well be worth the money in my case.

http://www.batterystuff.com/battery-...S12vProSP.html