How do you perform a functional test of an Automatic Transfer Switch (ATS)?

Performing a functional test of an Automatic Transfer Switch (ATS) primarily involves verifying its operation by simulating a failure of the primary power source. This is typically achieved by disconnecting the primary power source and monitoring whether the ATS automatically switches over to the backup power supply, such as a generator.

This process is crucial for ensuring that the ATS can effectively respond to power outages as intended. It assesses the switch's ability to detect loss of normal power and activate the generator, ensuring that backup power is supplied seamlessly. Testing the ATS in this manner also helps to confirm that the system can handle the load it is designed for and that the transition back to the primary power source occurs smoothly once power is restored.

While other options may contribute to the overall maintenance and health of power systems, they do not specifically evaluate the ATS's operational integrity in a functional context. Monitoring fuel levels and adhering to a regular maintenance schedule are important for system reliability but do not directly test the switch's automatic response capabilities. Similarly, testing with manual controls does not reflect the automatic functions that are essential to the ATS's design and purpose.