What action is recommended if voltage is declining in a known weak area after exhausting reactive resources?

When voltage is declining in a known weak area and reactive resources have been exhausted, the most prudent action is to manually shed enough load to prevent voltage collapse. This approach allows operators to quickly reduce the demand on the system, which can stabilize local voltage levels. By decreasing the load, the remaining infrastructure can more effectively manage the voltage, thereby avoiding a potentially catastrophic event where voltage levels drop below critical thresholds.

This action is essential in maintaining system reliability and ensuring that other, potentially more stable areas of the grid do not experience cascading failures due to the initial voltage decline. Manual load shedding is a direct and swift response that can be tailored to the immediate needs of the system and the specific conditions at play, making it a valuable strategy during periods of voltage instability.

In contrast, the other options do not address the immediate need to stabilize voltage effectively. Calling customer service or notifying customers of a shutdown does not actively mitigate the issue at hand. Allowing automatic undervoltage load shedding may not respond quickly enough to the rapidly declining conditions, possibly leading to more severe problems. Opening circuit breakers feeding all transmission lines would likely worsen the situation by removing necessary supply and could lead to broader outages. Therefore, the recommended action involves directly managing the load to protect the system’s integrity