On May 15, 8:19*pm, "Ulysses" wrote:
"BetaB4" wrote in message

...





I posted a question in the newsgroup "rec.boats" about recharging a
lead-acid battery for an electric boat motor after returning from a
boating/fishing trip. *The original question was about whether it's okay
to
leave the battery charger on for a few days to a week. *I found out that,
unless I have the more modern automatic type of battery charger, that is a
bad idea -- due to overcharging the battery.

Then someone suggested just plugging the battery charger into a timer and
setting the timer to turn the power off to the battery charger after say
12
hours.

My question now is,

"If I do the timer idea, could the fact that the battery charger will
still
be set to "ON", and will still be connected to the battery after the timer
cuts power to the battery charger, cause the battery to discharge and
drain
back through the battery charger?"

I tried a Google search but didn't find too much info that I could use.

I'm sure (well, pretty sure), as others have pointed out, that any draw from
leaving it connected to your battery would be insignificant. *But since I'm
too lazy to actually check it I disconnect the charger from the battery when
done. *Hell, I might foget about it for weeks or more.

As ransley stated you really need to know your charge voltage and charge
rate and duration to properly care for your batteries. *This info is usually
available from the manufacturer. *Some "Smart Chargers" are probably pretty
safe to use in general but some other "Automatic" chargers may ruin your
batteries in a fairly short time.- Hide quoted text -

- Show quoted text -

Years ago I got a "great" charger, only to find out many years later
it was never calibrated to charge 100% or went out of calibration, My
batteries never lasted or turned over the car when -20f. One day after
learning about what 100% charge is I luckily inside found a screw that
adjusted the voltage up. I think most new units are computer chip and
probably unadjustable. Not having a battery maintainer has ruined many
batteries for me.