Richard (the original) wrote:
I've had a SmartUPS 700 in service since 1999 and replaced the batteries
(2 12v Gel) with generics from Zbattery for about $20 each, no problem.
Different UPS's will produce different types of waveforms and this
can cause problems with some power supplies.

Here's some graphic pictures to illustrate what I mean by waveforms (I
was happy to see the Smartups puts out a true sinewave vs the chunky
stepped wave of the cheaper models)...

I was really unhappy with my SmartUPS 700 the morning it woke me up to
the sound of the gas alarm in my house. Thoroughly overcharged and fried
the six-month-old batteries. Trashed the gas alarm, too.

I replaced the 700 with a TrippLite that probably has a modified square
wave output, but no hydrogen or sulfuric acid fumes.

--
"Liberals used to be the ones who argued that sending U.S. troops abroad
was a small price to pay to stop genocide; now they argue that genocide
is a small price to pay to bring U.S. troops home."
-- Jonah Goldberg