On Wed, Oct 9, 2024 at 10:27 AM, Mike EI9FEB wrote:
PS / Alarm / Security / Emergency light gel packs are the worse as the assumption is that they are not regularly deep discharged. One or two deep discharges destroys them.
These devices do destroy gel cells that have been discharged, but there's two
ESSENTIAL conditions here that need to be understood as to why.
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1 - A too deep discharge below about 10.5v without them being re-charged
is the killer. Assumes something like a 12v gel cell.
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and
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2 - The crappy inbuilt chargers dont have the current limiting, and the gel cell gets
a what of maybe 1.5 - 2 amps before settling down after about an hour or two.
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It's too much for the batery chemistry to survive, and should ALWAYS be limited to
1/10th of pack capacity. All it needs is a current limiting resistor, and my experience
of things like UPS's and emergency lights etc has shown that they never bother
to include this vital but utterly essential component.
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Please please re-read my advice ;-)
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If you don't observe thes rules then you kill the pack, simple.
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73 de Andy
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