On 11/26/2014 09:30 AM, KenK wrote:

While trying to come up with something more to worry about, I thought of my
backup battery. I have a 12 v deep discharge lead acid battery with a
Battery Tender wall wart charger. I check the battery water level monthly
(usually) and keep an eye on the charger indicator light. I see no problems
but wonder if there was an easy way to be sure the battery will be charged
when the power goes out and I need it for a light and, if summer, a fan.
Just trust the charger to detect a problem and warn me by changing the
light color or blinking? An easy test of some sort, other than turning the
light and fan on for a half day or so every few months? I suspect I'll just
have to take my chances.

http://www.iotaengineering.com/pplib/spec2.pdf

And add the IQ4 smart-charge module.

Connect an el-cheapo multimeter (Hazard Fraught or the like) across the
terminals (permanently) but turn it on only to check the voltage from
time to time.

Perce