In case of a protective relay or equipment failure reducing system reliability, the Transmission Operator must notify which parties?

• A. Reliability Coordinator and affected Transmission Operators and Balancing Authorities
• B. Generator Operator only
• C. Adjacent Transmission Operators only
• D. No notification is required

Answer: (B)

The main idea being tested is who must be told right away when a protective relay or equipment problem reduces system reliability, so the party that can take immediate corrective action is notified quickly.

The correct choice reflects that the Transmission Operator is required to notify the Generator Operator. The reason is that when a disturbance like a relay or equipment fault reduces reliability, the quickest and most direct way to mitigate the impact is for the generator operator to adjust generation (or implement pre-agreed actions) to maintain power balance and reliability. This notification directly enables the generation fleet to respond to the changing conditions on the network.

Notifications to Reliability Coordinators, Balancing Authorities, or adjacent Transmission Operators are typically handled through broader operating procedures or automatic monitoring channels, or are triggered in more extensive or regional disturbances. In this specific situation, the emphasis is on informing the party that can promptly counteract the reliability impact—the Generator Operator—making that the best answer for the scenario described.