- WHAT is it - Online UPS is a UPS technology or approach to handling how the UPS acts during an event. Regular UPS technology (called line interactive) sense a loss in power and switch to battery power. This switch happens in 5 milliseconds. Online UPSes are essentially always using battery power to operate so they never "switch" power. Further, while regular UPSes can take some "dirty" power before switching over to clean battery power, Online is always providing clean power. According to Wikipedia Online UPSes main advantage is UPS is its ability to provide an electrical firewall between the incoming utility power and sensitive electronic equipment. Bottomline, Online UPS are better, but are more expensive. ($439 v. $595)
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- WHY you DON'T need it - Almost everything electric is designed to work on our dirty electrical power grid. So if you just want your stuff to work, Online's super clean power really isnt needed. Further, the 5ms switchover is more than fast enough to keep your equipment humming. As for surge protection, both systems are pretty pathetic. Its best to get a panel mounted unit as I dont know if that "firewall" can really hold up to a doozy.
- Why you MIGHT need it - If having a clean sine wave waveform is important, such as in instrumentation or equipment designed for the lab, then its worth it. Also if you have a backup generator, its best to go with a Online UPS because you really need the firewall with the atrocious power those generators put out.
If you need one, my store has a page for them
