A protective relay primarily functions to do what?

A protective relay is designed primarily to monitor electrical systems for abnormal conditions, such as faults, and to initiate protective actions when those conditions are detected. This main function ensures the safety and stability of electrical systems by detecting fault locations, which allows operators to address issues quickly and minimize damage or outages.

While detecting load variations, measuring voltage levels, and providing backup power are important functions within electrical systems, they are not the primary role of a protective relay. Load variations are typically managed by other devices, while voltage measurements are handled by voltmeters or similar instruments, and backup power is provided by uninterruptible power supplies or generators. Therefore, the ability of a protective relay to accurately identify and respond to fault conditions is crucial for the overall protection of the electrical infrastructure.