Re: APC Batteries.

["domdevitto" <dom@xxxxxxxxxxx>]

Nope,
I use a car charger to bring the batts to 100%, connected them to the
UPS and immediately after the first full 'to switchoff' use, neither
the UPS, nor a car charger could bring the batts back to life :-(

Oh, one *vital* point, for anyone as crazy/stupid/intrepid as me, UPSs
are not designed to run on batts forever - the bypass circuits are
often not thermally stable.  this means it'll get hot, possibly -
depending of ambient temp - too hot and burn out.  I think running a
UPS700inet for 2 hours was pretty much breaking point - the circuit
temp was very hot, but stable.  Normally you could expect 30 minutes
of load going through the UPS circuitry, so was running 4 times that,
just.  But it was the batts that died, not the UPS circuitry.

Note: Acid-filled boxes, high currents, sparks, hydrogen and very hot
electronics are not a great mix.

I would say that modding a UPS3000, or other UPS that is designed for
external 'daisy chained' batteries is a *much* better idea, as
deep-cycling is going to be harder/longer, and the circuitry is much
more likely to:
a) be thermally stable and
b) use higher quality components, designed to handle higher loads for
longer - e.g. not die after 3 hours of providing current.

I believe, from the last time I was at a datacentre (yesterday!), that
'proper' UPS tend to use lead-acid (same as car batteries) purely for
price, but I guess the circuitry switches off well before they are
deep cycled [the generator should be up after a minute or so].  This
makes sense, as gel-cells are more than twice the price, and space
isn't a problem for building-wide UPS.

Dom 'don't do this as home' De Vitto

--- In ukha_d@xxxxxxx, "Andy Whitfield"
<andywhitfield2002@...> wrote:
>
> The UPS would have switched off way before the batteries were deeply
> discharged.
> I'm guessing you left them discharged for a while before trying to
> charge them?
> Never leave lead acid batteries discharged for more than a day or
> two.
> Andy
> --- In ukha_d@xxxxxxx, "domdevitto" <dom@> wrote:
> >
> > <idiot alert!>
> > I modded a 700 to use 2x 12v car batteries, in series, and got
> great
> > run time (over 2 hours, on my rack), but the first really deep
> cycle
> > killed both the batts.
> >
> > The APC 700s are pretty smart, and learn the charging profile of
> the
> > batts, but it'll still let them discharge fully - which in my
case
> was
> > too much.
> >
> > Gel cells don't mind deep-cycle, so this should work perfectly.
> and
> > you don't need any baking powder :-) [don't ask!]
> >
> > Dom
> > --- In ukha_d@xxxxxxx, Wayne <Wayne@> wrote:
> > >
> > > Hi all,
> > > I have a APC SmartUPS 700 with batteries that the APC thinks
> needs
> > to be
> > > replaced. I have managed to get hold of a set from an APC
> SmartUPS 750.
> > >
> > > Does anyone know if they are compatible at all?
> > >
> > > They physically fit the UPS and seem to charge and keep the
> power to a
> > > pc when I pull the mains connection. The only thing that
seems a
> little
> > > 'odd' is when I pull the power and go onto battery, the ups
> normally
> > > beeps to let you know something not right - which it now
doesn't
> > seem to.
> > >
> > > One other difference - the newer battery set had a connector
> block that
> > > was attached to the battery red/black spade connectors -
when
> they were
> > > pulled from the 750 it has what looked like a 'quick
connector'
> > block at
> > > the back of the battery bay. My 700 just has two leads that
> connect to
> > > the black/red battery terminals that disappear into the
ups..
> > >
> > > There isn't any markings on the newer set of batteries that
> suggest
> > size
> > > or rating otherwise I could compare.
> > >
> > > any ideas?
> > >
> > > Cheery
> > > Wayne.
> > >
> >
>