Paper 2: Signalling and Telecommunications Works on the Euston Main Line Electrification

Abstract

The basic requirements of the signalling and telecommunications scheme are presented in this paper. Details of maximum speed of various types of trains, average headway, desirability for consistency of aspects, all necessitated the provision of four-aspect colour-light signalling with continuous track circuiting. Originally, power signal boxes with limited range were programmed, but economic conditions necessitated reconsideration for some electromechanical boxes. Difficulties arising in the manning of the signal boxes later caused replanning for power signal boxes throughout with much longer sections controlled from each box following technical developments. Particulars are given of the telecommunications requirements in principle. The planning of the signalling and telecommunications schemes are dealt with in some detail with special reference to the various factors to be met. Sections of the paper deal with design factors and equipment both for signalling and telecommunications with special reference to the methods which had to be adopted to give immunization against inductive effects from the 25 000 V 50 c/s traction system. Particular reference is also made to the instances where other electrical factors had to be met. Developments which occurred during the progress of the scheme are detailed and their effect on the original design is mentioned. The planning and execution of the installation work and the testing and commissioning are described, with some reference to the maintenance of the works. At the end of the paper reference is made to present-day experiences and some remarks are presented about the future.