If your are searching for BS numbers for old Isolators, and Protection devices which are now redundant then here is a few from the past
BS 5419 1977 wylex Isolator 100A
BS5419 1977 Wylex Isolator 60A
BS 861 Part 2 1972 BS 861 Part 1 1955 no image Yet
BS 4293 30mA Wylex RCD
The old crabtree C50 MCB BS3871 type 2
The Dorman Smith Loadmaster M3 BS3871