When should supervisory OPEN controls be performed on all open breakers?

Supervisory OPEN controls should be performed on all open breakers before energizing a substation or line to ensure the system's safety and reliability. This action involves verifying that all breakers are open as intended prior to introducing voltage to the system. By checking this status, operators can prevent potential faults, such as unintended feedback or equipment damage, that may occur if breakers that should be open are inadvertently closed.

This practice is critical for maintaining operational safety, especially in a high-stakes environment like a substation where proper configuration is necessary to protect both personnel and equipment. Ensuring all breakers are open aligns with operational protocols that emphasize precautionary measures prior to energization, fulfilling a key aspect of system protection standards.

Other options, while they may involve important operational procedures, do not hold the same priority or immediacy as checking the status of open breakers before introducing power. For instance, performing these checks after major upgrades or during maintenance schedules involves different contexts where the emphasis may shift towards verifying upgraded equipment or carrying out necessary repairs rather than focusing solely on the breaker status prior to energization.