What is the primary function of an automatic transfer switch (ATS) in a hospital's emergency power system?

The primary function of an automatic transfer switch (ATS) in a hospital's emergency power system is to automatically switch the electrical load from the normal power source to the emergency power source (typically a generator) in the event of a failure or disruption of the normal power supply. The ATS continuously monitors the voltage and frequency of the normal power source. If the ATS detects an undervoltage, overvoltage, or loss of power, it automatically disconnects the load from the normal power source and connects it to the emergency generator. This ensures that critical equipment and life-support systems continue to receive power without interruption during a power outage. Once the normal power is restored and has stabilized, the ATS automatically transfers the load back to the normal power source. The ATS operates without human intervention, providing a seamless transition between power sources. This is crucial in hospitals, where even brief power interruptions can have life-threatening consequences for patients.