Which device automatically transfers loads to standby power during a utility outage?

• A. Manual transfer switch
• B. Automatic transfer switch (ATS) routes loads to standby power during a utility outage.
• C. Voltage regulator
• D. Fuse

Answer: (B)

Automatic transfer switching is what keeps critical loads powered during a utility outage. An automatic transfer switch constantly monitors the utility voltage and, if it drops or becomes abnormal, it instantly shifts the load from the utility supply to the standby generator. This happens automatically, so there’s no need for a person to intervene and no noticeable power gap for most loads. A manual transfer switch would require someone to flip the switch, causing delays. A voltage regulator only fixes voltage levels on a single source, not switching between sources, and a fuse is a protective device that interrupts current during faults, not a means to transfer loads to standby power.