What is the role of protective relays in switchgear?

Protective relays play a critical role in switchgear systems by detecting abnormal conditions such as overcurrent, undervoltage, ground faults, and other electrical anomalies within the electrical network. When these relays identify a fault or an operational issue, they send a signal to the connected circuit breakers to initiate a disconnection of the affected circuit. This action is vital for protecting not only the equipment but also the safety of personnel working near or with the switchgear.

By responding quickly to these abnormal conditions, protective relays prevent potential damage to electrical components and reduce the risk of hazards, such as electrical fires or equipment failure. This functionality is an essential aspect of maintaining system reliability and ensuring safe operation in electrical installations. The ability of protective relays to make intelligent, real-time operational decisions is what separates them from roles such as amplification of signals, visual indicators, or energy storage, which do not contribute directly to system protection.