Confirm that the input signals are within the relay's specified ranges and investigate any abnormalities. Analyze fault records or event logs: If available, review any recorded fault events or relay operation history. The testing and verification of relay protection devices can be divided into four groups: Type tests are needed to prove that a protection relay meets the claimed specification and follows all relevant standards. Since the basic function of a protection relay is to correctly function under abnormal. Protective Relays - Technical Seminar Nov 2016 - Copyright: IEEE 2 Abstract: Protective relays and devices have been developed over 100 years ago to provide “lastline”of defense for the electrical systems. They are intended to quickly identify a fault and isolate it so the balance of the system. Selectivity is a mandatory requirement for all protection, but the importance of it depends on the application. For example, unselective protection operation during a medium voltage network fault will cause an outage for an unnecessarily large number of consumers. In actual use, various abnormal phenomena may be encountered. However, relay malfunctions can occur, which can lead to incorrect. Second, the relay protection system fault treatment methods and measures 1, the common treatment method of relay protection failure 1) Alternative methods Replacing the faulty unit with a complete unit and judging the quality of the faulty unit can quickly reduce the scope of fault search; 2).
