NR SSIDIS145 APP C ISSUE 2 PDF

Introduction

This paper has been prepared to propose and gain acceptance for a method of implementing Stopping/Non-Stopping (SINS} controls in an MCB-CCTV level crossing.

The background to the requirement for this paper is the introduction of Rigton MCB-CCTV crossing in the Harrogate Area Signalling Renewals project. This crossing is being controlled using SSI as the transmission medium between the level crossing control panel in the signal box and the crossing circuits trackside (i.e. as described in sections 4.1 and 5.1 of OIS145 issue 4), with IECC being the signalling control system. The crossing SSI data and circuitry are therefore being designed as defined in the main OIS145 document. However, Rigton MCB-CCTV is also required to have SINS controls, which are not covered by the main document. This paper therefore proposes a method for SINS controls to be added to the comprehensive data and circuitry methods given, and is to be read in conjunction with the main document. As such, the examples given will be based on extending the existing examples, rather than a completely new layout depicting the actual Rigton MCB-CCTV.

Although guidance for AHB SINS controls has previously been provided in several documents within the SSI Applications Manual NRIL21SIG/17002, they are not directly suited for application on MCB-CCTV, as will be demonstrated below. A method for SINS controls in MCB-00 applications was proposed in OIS174, and although some parts of this are relevant to MCB-CCTV, they may not all be suited to the application at Rigton, because of a difference in train (strike-in) detection methods. The approach in this paper will therefore be based on selecting relevant portions from the various sources of guidance above, amending or adding to them as may be necessary, and putting them together to form a comprehensive solution, providing any necessary justification for the choices made.

It is worth noting that principles for SINS controls in MCB-CCTV (unlike those for SINS controls in AHB) are not laid down in any Network Rail standards; whether SSI data standards, relay typical circuits, or higher level MCB-CCTV requirements specifications.