[ale] OT: question about replacing batteries in a APC UPS

[Mike Harrison]

> Pardon my ignorance, but what kind of tester are you recommending, how 
> does it work and what does it test for, please ?

My guess is a 'three light outlet tester'.. and although I'm proud of
my Fluke and Tektronix gear, a $20 generic digital volt meter is often 
overkill for the job and much more useful if you take 5 minutes to learn 
how to use it. It's also very useful for other things.. fixing Christmas 
tree lights.. etc.. 

And to be on-topic: http://linux-gpib.sourceforge.net/
supports popular GPIB cards (National Instruments is pretty common)
so you can communicate with GPIB (IEEE-488) enabled meters, 
oscilliscopes, and other devices (even some camera's!)

Then you plug a IEEE-488 enabled voltmeter/scope to your incoming power, 
and you can record voltage fluctuations or other environmental factors.

We used to have a junk system running Linux wired up to monitor and record
incoming AC power and environmentals (temp/humidity). It forced
the local Electric Power Board to replace the transformers feeding our 
building, which solved some intermittent power and brownout conditions.

--

btw.. if you don't occaisionally exercise (unplug the UPS
and let it run a while draining down the batteries) your UPS, the 
batteries get 'flat'. They look charged, but have little capacity 
because of the buildup of crud accumulated on the plates. Higher-end
UPS's even have built in exercise routines. - Running them down 
every once in a while burns off the buildup from being in a charge state
for months.