On 03 Feb 2009 01:34:13 GMT, Warren Post wrote:

I just replaced the battery in my UPS, and notice that the old one was
swollen and hard to remove. Searching this NG and elsewhere on the net, I
see this means that the battery had reached the end of its life some time
ago and should have been replaced sooner. Okay, replacing the battery
when it reaches the end of its life cycle instead of waiting until it
obviously fails is fine by me.

So how do I know when to replace a UPS battery? This particular UPS has
no self test feature and no com port with which to communicate with the
computer, and I don't want to toss perfectly working equipment into the
landfill just because it lacks bells and whistles to make my life a
little easier.

Check the data sheet? I just had to replace the battery in my home setup
UPS and noticed that the datasheet for the replacement states "For main
and standby power supplies. Expected trickle life: 3-5 years at 25C,
Approx 5 years at 20C." (Panasonic LC-RA1212P)

Actual lifetime would depend on the quality of the trickle charge, how
often and for how long it's called upon to supply power, as well as how
hot it gets.

Absent a test circuit in the UPS, your best bet would be something like
a semi-annual load test, plotting the time-to-dropout versus lifetime.

--
Rich Webb Norfolk, VA