scope:

This part of IEC 60255 is based on IEC 61000-4-18, referring to that publication where applicable, and specifies the general requirements for 1 MHz oscillatory wave immunity tests for measuring relays and protection equipment for power system protection, including the control, monitoring and process interface equipment used with the relays and protection equipment. The objective of the tests is to confirm that the equipment under test will operate correctly when energised and subjected to repetitive damped oscillatory waves such as those originating from closing or opening circuit breakers or disconnectors in high voltage substations or power plants. The requirements specified in this standard are applicable to measuring relays and protection equipment in a new condition and all tests specified are type tests only. The object of this standard is to state: - definition of terms used; - test severity levels; - test equipment; - test set-up; - test procedure; - criteria for acceptance; - test report.