Fried UPS

Tried to access our home network drive and there was no answer. Suspecting a loose network cable or switch that needed a reset, I head into the office and notice right away that the UPS under the office desk is blacked out. Did one of the cats knock the power cord loose?

I jiggle cords, press power buttons, no joy, so I take the UPS out into a open well-lit area so I can check her out. I pull out the batteries, thinking they might not be holding a charge anymore (this UPS is about 6 years old), and this is what I see:

Something toasted inside the unit and left char all inside the unit. Interestingly, there’s no smoky smell, or even that typical scent of “uh oh” ozone that anyone who has every dabbled with electronics will know. Just this gray soot over the inside of the box.

I just replaced it with another unit (is 6 years a long time for a UPS?), but am not wondering if placing it under a flammable desk is the best location for it.

Wow! Not what I would have expected. Did the batteries appear damaged? Chemical burn?

Batteries seemed fine, no leaks or cracks, terminals were nice and clean - nothing funny that I could tell. They were only holding 6.5V (12V batteries), but that could have been either the result or the cause of the issue.

I gave the batteries to a recycle place but am going to tear apart the unit, try to salvage useful bits from it. UPSs usually have great chokes and caps - just need to make sure they still work.

Testing out mine as we speak…gotten quite a few nearby lightning strikes and some power flickers…

Years ago one of my ups units failed. Something rattled around in it - a 50 watt ceramic resistor had gotten so hot it desoldered itself from the circuit board! All of my many computers have had a UPS and the Cyberpower brand is a good choice IMO.