On 11/26/2014 10:00 AM, philo wrote:
1) You should not be charging a "wet" type lead acid battery in-doors,
the hydrogen emission is explosive. The type of battery you should be
using in your house would be VLRA. (Valve regulated lead acid.)

2) Since most people ignore my first point when I warn them, the type of
charger you use /can/ make a difference. Ideally you'd want to employ
hysteresis-loop charing techniques. This type of charger only charges
between preset voltage ranges and minimizes water consumption and
maximizes battery life. You are unlikely to find such a charger in the
"consumer" market...so the next best thing is a "float" charger which
will retain a constant voltage just below the battery's gassing point.
What you do not want is a "trickle" charger. That type simply puts out
an /unregulated/ small amount of current.

3) There are testers that can check a battery's internal resistance
without actually putting a load on it. They are fairly reliable but the
only sure way is to actually load it down. A reasonable test would be to
simply place a heavier than usual load on it for a relatively short
period of time and check the voltage drop. If the battery can stay above
11 volts under a heavy load it's probably fine.



Additionally: If you do insist on using a "wet" type battery my advice
would be to /not/ keep it on charge. Unless there is a load on it, it
may only require a "top off" every three months or so. The charging area
should be well vented.


My credentials:

I worked for Enersys as a Senior Service Engineer & retired after 38
years. Many a time have I seen exploded batteries and I did so myself
exactly once.


The one exploded battery I've known in person was
an old farmer trying to start a Gehl Skid Steer.
He had the battery on 12 volt boost. He went to
adjust the battery clamps with the charger still
on / plugged in. I was on the other side of the
machine, but I remember his words "get some water
for my eyes".

The Op's float charger won't make enough hydrogen
to do that.

-
..
Christopher A. Young
Learn about Jesus
www.lds.org
..