A UPS does one job: it keeps equipment running long enough to shut down properly, or long enough for the generator to pick up. Anything beyond that is an inverter, and the two get confused at the point of purchase more than any other pair in this catalogue.
Sizing needs two numbers and most enquiries arrive with neither. The first is the load in watts - not the sum of what is printed on the equipment, which is nameplate maximum and usually double what a machine draws. The second is the runtime you actually need, which for a generator changeover is two minutes and for an orderly server shutdown might be fifteen.
Line-interactive units suit desks and small network cabinets. Online double-conversion is what a server room or anything with a sensitive power supply needs, because it rebuilds the waveform rather than filtering it, and Nigerian mains often needs rebuilding rather than filtering.
Batteries are the consumable. They are typically good for three to five years in an air-conditioned room and considerably less in a hot one, and a UPS with dead batteries reports itself as healthy right up to the moment it is needed. Budget for replacement rather than for the unit alone.
Tell us what is plugged in and how long it must stay up, and we will size it.
