NR SAO-IEC-TG-7 ISSUE 4 PDF

Introduction

Automatic Route Setting (ARS) is a system to be used within a railway signalling and control centre to assist the signaller by performing functions such as setting routes for trains and monitoring the state of the railway.

In general ARS will be installed as a subsystem within an Integrated Electronic Control Centre (IECC). ARS has also been installed as part of the Waterloo resignalling scheme where interface processors are used to provide an IECC-like interface to ARS.

ARS has been designed with the aim of providing a general system of widespread applicability on the Network Rail network. Nevertheless, prior to any particular implementation of ARS, a Specification of Operating Requirements should be produced by Operating staff. This will contain the information necessary to configure ARS to operate in that particular area, in the same way that the Signalling Control Tables configure the interlocking and the Stepping Tables configure the Train Describer.

ARS is a complex system and so information on various aspects of railway operation is required. This Guide to the Specification of ARS Operating Requirements describes the various aspects which should be considered and the items of information which should be supplied. Much of the information is in the form of data TABLES, but in some cases explanation of particular DETAILS is necessary. Any additional information or comment relevant to the ARS requirements should also be included.

Some operators may feel that the approach described in the Guide is unfamiliar and does not readily correspond to the method they would use to describe the ARS operation. In this case it may be best to first produce a document defining all of the relevant factors in more familiar terms. However, it is recommended that in all cases a document of the form defined in this Guide should ultimately be produced. This will have the following advantages :

(1) by following the order in which the Guide discusses the relevant factors, an understanding of the way in which ARS works will be achieved.

(2) a standard form for the specification of operating requirements will assist the Signal Engineers in determining what is required, and should produce a document which can be understood and agreed by all concerned, thereby reducing the risk of misunderstanding between the operators and signalling contractors.

(3) considering the aspects in a fixed order should ensure that no relevant factor is omitted.

Once the Specification of Operating Requirements has been produced then the data preparers will be able to prepare the necessary data to configure the ARS system. In some cases they may find that a requirement has been specified which can only be met by a modification of the existing ARS system and in this case the Network Rail Zone in collaboration with Network Rail HQ will have to review the requirement against the modification cost.

Section 2 of this Guide describes the aspects affecting ARS train regulation and routesetting and section 3 describes those aspects affecting the train monitoring and alarm features of ARS.

Within the IECC, ARS works closely with a Timetable Processor (TTP) which supplies it with train timetable information. ARS also obtains signalling state information from the interlockings and train position information from the Train Describer function in the Signaller’s Display System. The Signaller’s Display System may be a Signalling Display Subsystem (SDS) or Flexible Display Subsystem (DIS). Section 4 covers those aspects of the interface between ARS and these other systems which need to be specified.

It is recognised that this Guide will not cover every possible situation which may arise throughout the Network Rail network.