Analysis of failures of bushings in english electric 25kV K-11 switchgear (TN-ETR-002)

A total of 506 units of K-11 type 25kV switchgear are installed on L.M.R. Euston/Liverpool/Manchester electrified system. The switchgear was installed over the period 1959-1967. In 1967 audible discharge was reported on O.C.B. E/EA-5 at Euston T.S.C. and in February 1969 the cable side bushing (CS) was replaced by a...