The Southern Railway (SR) gave the designation CW to the fleet of AC electric multiple units used on line between Coulsdon and Wallington.

Construction

The CW (Coulsdon and Wallington stock) units were built in 1923-1924, as the last electric train stock for use on the LBSCR AC overhead electrified lines in South London. This stock comprised of some hundred carriages, which were used in five car formations (Driving Trailer + Trailer + Motor Luggage Van + Trailer + Driving Trailer).

After the replacement of the AC overhead equipment by the 750V DC third rail system adopted as standard by the SR, the carriages that formed these units were rebuilt accordingly.

Formations

Initial formations of these units were as follows: