Failure of high speed section insulator at Hanslope 1971-1977 (TM-ETR-092)

There are six high speed section insulators (H.S.S.I.) in the fast lines at Hanslope, near Northampton, which provide electrical sectioning of the overhead system during maintenance (Fig.1). Four of these are in crossovers which operate at speeds of up to 110 km/h. The other two are in the Up Fast...