Learn in the textbookFacility Management: Power Supply Measures and Energy Saving
DefinitionAn uninterruptible power supply (UPS) (無停電電源装置) uses power stored in its built-in battery to keep feeding equipment for a while even when an outage or a momentary voltage dip occurs.
ExplanationHow long it can keep supplying power depends on the battery capacity, typically from a few minutes to a few tens of minutes. Keeping the buildings and equipment that run information systems in good condition is called facility management (ファシリティマネジメント), and maintaining power equipment is one of its main targets.
AnalogyIt is like the emergency lights that stay on for a while in a building during a blackout. They give you time to calmly wrap things up and get outside before everything goes dark.