What type of UPS provides the most immediate power restoration during an outage?

Choosing an Online UPS as the type that provides the most immediate power restoration during an outage is based on its operational characteristics. An Online UPS continuously supplies power to the connected load from its inverter without relying on the utility supply. It does this by constantly charging its batteries while simultaneously supplying power, which means that there is no break in power when an outage occurs.

When a power disturbance happens, the Online UPS seamlessly continues to provide power as there is no switchover time, making it ideal for critical applications that require constant, uninterrupted power such as data centers and critical network equipment. The design allows for instant power restoration without any latency, ensuring that operations are not disrupted.

This contrasts with other types of UPS systems, like Standby or Line-interactive UPS, which switch from utility power to battery power during an outage. These systems can introduce brief interruptions during this transition, which can be problematic for sensitive equipment or data integrity. A Fast Transfer UPS is not a standard classification used widely in UPS technologies to categorize power backup systems based on performance during outages, and thus would not be the correct selection based on typical UPS categorizations.