25 kV a.c. conversion, liverpool street to Gidea park E.R. Current collection performance of a triple contact wire bridge arrangement and the brown boveri section insulator tested at Widmerpool May '77 (TM-ETR-098)

The Liverpool St.-Shenfield line was originally electrified in 1949 at 1 500 V d.c, using heavy compound fixed-termination overhead equipment. It was converted to 6.25 kV a.c. in 1960, retaining the original bridge arrangements except for larger insulators. The Gidea Park-Shenfield section, which has few bridges, has been converted to...