What is the main function of disconnect switches in switchgear?

The main function of disconnect switches in switchgear is indeed to isolate circuits for maintenance or safety. These switches are designed to completely separate parts of an electrical circuit, ensuring that maintenance personnel can safely work on electrical equipment without the risk of electric shock. By providing a visual break in the circuit, disconnect switches help ensure that no unintended electrical energy is present when maintenance is occurring, thereby enhancing safety protocols in substations and other electrical installations.

While other options describe important functions related to switchgear and substations, they do not accurately represent the primary purpose of disconnect switches. For example, automatically shutting down a substation pertains more to circuit breakers or relays, which respond to faults or abnormal conditions. Regulating voltage output from power transformers describes the function of voltage regulators or tap changers, not disconnect switches. Lastly, connecting and disconnecting power generation sources refers to circuit breakers or connecting switches, which handle the energization or de-energization of circuits, rather than providing physical isolation for maintenance purposes.