IEC 60255-1:2022 specifies common rules and requirements applicable to measuring relays and protection equipment, including any combination of equipment to form a distributed protection scheme for power system protection such as control, monitoring and process interface equipment . IEC 60255-1:2022 specifies common rules and requirements applicable to measuring relays and protection equipment, including any combination of equipment to form a distributed protection scheme for power system protection such as control, monitoring and process interface equipment . 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. While this is bad, It's not a. imagination at workGEA-31959 GE Grid Solutions reserves the right to make changes to specifications of products described in this reference guide at any time without notice and without obligation to notify any person of such changes. © 2016 GE Grid Solutions GEGridSolutions. It integrates protection functions, measurement and telemetry, automatic. The International Electrotechnical Commission (IEC) is currently working on a new series of standards that covers the functional requirements of measuring relays and related equipment used to protect electrical transmission and distribution systems. The technical content of IEC publications is kept under constant review by the IEC.