In article ,
alan_m wrote:
The problem in alarm panels is the battery is never cycled - just
trickle charged 100% of the time. After a number of years the battery
still has the correct terminal voltage but cannot provide the
instantaneous backup power when the mains fails.

Assuming an SLA, they don't need cycling. What you are talking about is
suphation of the plates, and if that has happened the battery is basically
scrap.

--
*If you ate pasta and anti-pasta, would you still be hungry?

Dave Plowman London SW
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