On Sat, 2 Oct 2004 20:43:04 -0400, "John C. French"
wrote:
Could these new electronics
be draining the battery even when powered off, or could it just be time to
replace the battery? The battery never reads over 12.4 volts, even when
charging, and after a long day of fishing, the battery level will be down to
as low as 9 volts.

======================================

Sounds like it's time to replace. Batteries, even deep cycle
batteries, should never be discharged below 11.5 volts (half power).
Discharging them lower than that will severly shorten their life.

Actually, half capacity for a liquid electrolyte battery is 12.2 volts.
But in any case, based upon your description, they do seem to be
pretty bad off.

Doug
s/v Callista

"Wayne.B" wrote in message
...
On Sat, 2 Oct 2004 20:43:04 -0400, "John C. French"
wrote:
Could these new electronics
be draining the battery even when powered off, or could it just be time to
replace the battery? The battery never reads over 12.4 volts, even when
charging, and after a long day of fishing, the battery level will be down
to
as low as 9 volts.

======================================

Sounds like it's time to replace. Batteries, even deep cycle
batteries, should never be discharged below 11.5 volts (half power).
Discharging them lower than that will severly shorten their life.

On Mon, 4 Oct 2004 17:10:57 -0400, "Doug Dotson"
wrote:

Actually, half capacity for a liquid electrolyte battery is 12.2 volts.

=============================

Under what meausurement conditions? Can you cite the source of your
information? 12.2 volts (resting condition) is only 20% discharged
in my experience.

No, an open circuit voltage of 12.2 for a flooded battery usually means about
50%, or for a cruiser, time to recharge. Under load, of coarse, 12.2 could mean
about 80%; IIRC my house bank will drop to about 12.25V when the fridge is
running with its 30 Amp load.

http://www.trojanbattery.com/custome...erymaint4.html
http://www.rollsbattery.com/Bulletins/600.htm

"Wayne.B" wrote in message
...
On Mon, 4 Oct 2004 17:10:57 -0400, "Doug Dotson"
wrote:

Actually, half capacity for a liquid electrolyte battery is 12.2 volts.

=============================

Under what meausurement conditions? Can you cite the source of your
information? 12.2 volts (resting condition) is only 20% discharged
in my experience.