[rescue] [Slightly OT] Smart-UPS 1400 Battery replacement

[Brian Hechinger]

On Fri, Aug 03, 2001 at 08:54:31AM -0400, James Fogg wrote:
> 
> Assuming they are near discharge now....

they should be, this thing has been offline for a while now (it probably sat
where it was picked up from for at least a year or two before i got it, and
it's been sitting about 6 months in my possesion, i KNOW i should be floating
these things, but i just never got around to it.  maybe i should do that.

> 1) disconnect all the wires from the batts.

that's easy enough. ;)

> 2) measure the voltage on each batt, they should all be within 1/4 volt of the
> average of all their voltages (if not, deadsville).

that's gonna take one of the voltage measuring thingies, right? :)

but since they've been sitting for so long, would they even have any voltage
anymore?

> 3) if any batt is below .5 volt per cell, then the batts are gone. each cell is
> good for 1.5v, so if its a 6v batt, then thats 5 cells.

battery says 14.1V on it.

> 4) re-connect and charge for two days.

this is not going to be so easy.  the controller weighs close to 200 pounds and
the battery cabinet weighs over 600 pounds.  (although i can remove the
batteries and move it that way, although the frame itself is 150 pounds) i would
have to drag them into my basement since that is the only source of 220V (this 
is not a 110V item) and the basement access to this place SUCKS.  so that's not
gonna happen here.  i was thinking more along the lines of stringing up the 
batteries to a DC powew supply (if i can get a good one for a reasonable amount,
those HP units rock, but they are a bit pricey)

> 5) place a dead load (resistive load, like a bunch of light bulbs) on the ups.

uhm, 10KVA/7500W UPS.  i'd need, uhm, 75 100W lightbulbs.  YIKES!! :)

> Pull the ups plug and see if the ups has decent output (measure it and watch
> the bulbs). This is a cheatin way of measuring load capacity.

yeah, but it's the only way i have since i don't own any hardware that can 
create a high quality resistive load (like the stuff we had at Exide)

> 6) disconnect batts and measure for equality like in step 2.

am i under the same restrictions as before? (1/4 voltage and under .5v?)

the sad part is i used to do this for a living, but it's been so long i've
forgotten ALL of it.  *sigh*

-brian