Dynixis — Home Backup Power and UPS | dynixis.com
A table of UPS classes and battery options with typical runtime and what each one protects.
UPS units fall into three main classes by how power reaches the load. In an offline or standby unit, mains passes straight through and the inverter starts only when power fails. In a line-interactive unit the inverter stays ready and corrects small voltage swings without switching to battery. In an online double-conversion unit power is rectified and inverted continuously, so transfer is seamless.
Runtime depends on both class and chemistry. Offline units typically hold a full load for 5 to 10 minutes; line-interactive units commonly report 8 to 15 minutes at half load. Units with lithium-ion packs tend to run longer at the same footprint because the cells store more energy per litre.
Battery chemistry changes the physical trade-off. Sealed lead-acid packs are heavy but inexpensive per watt-hour and dominate larger units. Lithium-ion packs, whose energy density tripled and cost dropped tenfold since 1991, fit compact desk-side units where weight and volume matter.
On narrow screens, swipe or scroll the plate sideways.
Scale determines the class you need. Units range from devices protecting a single computer to units backing entire data centers. A plug-in unit for a router and modem may hold 5 to 8 minutes; a rack-mount unit with external battery strings can extend runtime to an hour or more.
For a home computer and router, a line-interactive unit in the 500–1500 VA class covers most loads within the standard 5 to 15 minute window. Check the runtime curve at your actual load rather than the figure printed on the box.
Compare the classes against your load before committing: the right class at the wrong rating still shuts down early.
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