Sakis is planning to implement a power conditioning UPS for a rack of servers in his data center. Which one of the following conditions will the UPS be unable to protect against if it persists for an extended period of time?

UPSs are designed to protect against short-term power losses, such as power faults. When they conduct power conditioning, they are also able to protect against sags and noise. UPSs have limited-life batteries and are not able to maintain continuous operating during a sustained blackout.