On Fri, 06 Apr 2018 15:17:34 +0100, "Dave Plowman (News)"
wrote:
In article ,
The Other Mike wrote:
On Fri, 06 Apr 2018 13:58:27 +0100, "Dave Plowman (News)"
wrote:
In article ,
Chris Green wrote:
Not really. A lead-acid battery should be charged to something like
14.5 volts to get it fully charged (and it's important to get them
fully charged sometimes). Then, when it's fully charged, the charger
should drop back to 13.5 volts or so to maintain the battery in
'float'. Most 'intelligent' lead-acid battery chargers will do
something like this, the 14.5 volts guarantees full charge but if
maintained long term will make the battery gas. Really clever
chargers will occasionally wake up out of float mode and do a sort of
battery conditioning sequence.
Very odd. SLA batteries have been charged at constant voltage for many
many years. What has changed?
Nothing except it allows the cells to be restored to full capacity quicker and
without damage. It's the kind of thing APC haven't been doing for over 25
years.
Page 22 "Two Stage Constant Voltage Charging"
https://news.yuasa.co.uk/wp-content/...5/NPManual.pdf
First page or so of that says it refers to spill proof wet electrolyte
batteries. Which are not gel type SLA. The type I'm referring to.
Didn't wade through the rest as I'm aware different versions of wet
batteries need different charging methods for best results.
I'd hazard a guess that the vast majority of what people regard as sealed cells
are actually Yuasa's or clones of Yuasa designs. Drop one on its corner and no
liquid actually spills out, actually there is no leakage of anything at all
Compare to a dryfit 'gel' cell from Sonnenschein and you'll see there is little
difference in the charging regime.
https://docs-emea.rs-online.com/webd...6b81270ea4.pdf
Yuasa (from the reference previously given page 23)
1st stage is 2.4-2.45v per cell
2nd stage is 2.27 v per cell
Sonnenschein
1st stage is 2.4-2.45v per cell
2nd stage is 2.3v per cell
30mV per cell difference when on float or 180mV per 12v nominal battery
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