Glossary A–ZLetter U
Uninterruptible power supply (UPS)
An uninterruptible power supply is a device with a battery that keeps connected equipment powered without interruption during a power cut or voltage fluctuations.
It bridges short outages and provides time to shut devices down in an orderly way. There are simpler and more elaborate designs, which differ in how well they protect against disturbances.
In screen networks, a UPS makes sense where an outage has consequences: for servers, network equipment, emergency or departure displays and Windows players, whose file system can be damaged by a hard shutdown. For each individual display in a shop it is usually not needed, but it is for the switch to which many devices are connected.
Operators should bear in mind that batteries age and must be checked and replaced regularly; a UPS that has never been tested often fails when it matters. Runtime depends on the connected load, and a large display drains the battery quickly. A UPS does not replace fault handling: devices should restart by themselves after an outage even without a UPS.