Standby UPS The most common in smaller systems is the Standby or Offline UPS. This is the one you would normally use on a personal computer for example. The Standby UPS lays in wait for its time to spring into action, and once there is a power failure, it takes control. The Standby UPS tends to be the most cost-effective UPS available. Watch the video and answer the question. When does the Standby UPS become active? Tag someone who needs to see this. #UPS #UninterruptiblePowerSupply #Automation