What are protective relays used for in electric systems?

Protective relays play a critical role in electric systems by detecting abnormal conditions, such as faults or imbalances in the current or voltage levels, that could pose a risk to the system's integrity and safety. When these devices identify such anomalies, they initiate corrective actions designed to isolate the problematic section of the system, thereby preventing damage to equipment and ensuring the overall stability of the electrical grid.

The primary function of a protective relay is to enhance the reliability of power systems by acting swiftly and effectively when issues arise. This can involve signaling circuit breakers to disconnect a faulty section from the rest of the network, which helps to minimize disruption and maintain service to unaffected areas.

Other roles, such as increasing electrical voltage, measuring current flow, or regulating temperature, do not encompass the primary purpose of protective relays, which is centered on fault detection and response. Those tasks are typically handled by different types of devices within an electrical system.