I was smelling burnt plastic for a week before I found the outlet on my Cyber-Power 550 VA UPS had turned to charcoal. I cleaned the cord and moved it to another outlet on the UPS. A week later, it still stinks. I pull it out of its lovely home in my hand made computer bench and the second outlet is showing changes. So I look inside. It was mounted with its "sealed" lead acid battery contained, terminals down. Autopsy found liquid acid in the outlet. Why would I mount a liquid acid container with its allegedly sealed holes facing down? Because that's how the mounting holes are designed on the back of the Cyber-Power 550. You can either have your SLA with its battery top facing down or to the side, but never on top. I must be getting old. I trusted a big name to make a smart design. I would never trust an acid container, no matter what anybody claims it will do, to not leak if you hold it up-side down for a year. So, I'm without a UPS right now. The next one will get inspected better! It will get mounted with the top of the battery facing up, regardless of how the OEM designed it.