ELECTRIC RAILWAY

Southland Times, Issue 20495, 25 May 1928, Page 11

ELECTRIC RAILWAY

TRAINS WITHOUT DRIVERS. Trains which cross London,. running at about thirty miles per hour between the stations and operated without drivers, are features of the Post Office (London) Railway which has just been completed. It connects Paddington Station and District Office in the West with the Eastern District Office, six and a half miles away, in the East, with intermediate connections at five important postal buildings, and with Liverpool Street Station. The guage is two feet, and between stattions the east-bound and west-bound tracks are contained in a single nine-feet tubular tunnel, which is generally at a depth of sixty to eighty feet below the ground level. Three-car trains are run, being 45 tons of mail matter per hour in each direction on any one section. The trains run at about thirty miles per hour between the stations, and are operated without drivers on the remote control system, protection being afforded automatically by the trains themselves in the sections between stations and in the neighbourhood of the stations by in-ter-locked gear in the control cabins. Each wagon’s equipment consists of two series motors in parallel, to which power is supplied through some resistance in series, and brake gear, applied by a spring and released by an electric solenoid, current being collected by shoes from a single central conductor rail and returned through the running rails, one of which is divided into sections corresponding with the conductor rail sections and track-circuited throughout. Following a train from station to station, it is despatched from a station section at 400 volts, runs at thirty miles an hour until it reaches a one-in-twenty up grade at the approach to the next station, when it runs on to a dead section of the conductor rail, the brakes are applied, and it comes to rest just outside the station. After a short interval an automatic motor-driven timelag device causes it to be energized again at 440 volts for some four or five seconds, after which 150 volts is applied, with the result that it enters the station at about eight miles an hour, and conies to rest in a few feet on entering the particular berth, the conductor rail of which has been made dead to receive it. The points are electrically operated, and are interlocked with the electrification of the different sections of conductor rail by means of a lever frame which embodies the general principles of railway practice.