NR NR/L2/SIG/11201/MODA18 ISSUE 6 PDF

This standard applies to all new suites of Control Tables written to define the controls required for signalling systems (electro-mechanical, electrical and electronic); however there are different Appendices relevant to each variety. Where alterations are being undertaken on an existing installation the former practice shall be perpetuated unless it is practicable to update and this would not lead to the risk of confusion between standards;

This standard does not include control tables for non-route setting systems; such control tables shall be based upon those given here, but with the route sheets adapted to suit signal interlocking and aspect controls. Similarly excluded are mechanical locking tables for lever frames of which there are different varieties in use; these reflect former regional practice and applicable to particular types of locking frames. However the standard does include the interface to Ground Frames and their electrical controls. Guidance on the presentation of mechanical locking tables is given in NR/GN/SIG/11701.

Although including some typical examples to illustrate the use of the control tables, this standard is not intended to prescribe the signalling controls that shall be applied within an interlocking system, but only the format in which they shall be presented.

The general presentation of design documentation is covered in NR/GN/SIG11701. It is not intended in this Code of Practice to prescribe the form of title block to be provided on each sheet, but only the information contained.

Examples of control tables for a typical layout (both route setting and lever frame) are included.

Where this standard refers to SSI, it applies equally to WESTLOCK and SMARTLOCK.

There are no specific control tables for the Ansaldo ACC system, or VHLC system and existing formats shall continue to be used.

Purpose

This Level 3 standard mandates the requirements for the presentation of railway signalling Control Tables to make sure that safety information is presented in a form which can be read and understood without ambiguity.

Control Tables define the manner in which the interlocking of a specific site is to be arranged and thus how Network Rail's generic Signalling Principles are applied to the particular track layout being considered. They thus form an intermediate step between the Concept Design (defined by such documents as the Scheme Plan and the various Requirements Specifications that stipulate the various outcomes expected from the project) and the Engineering Details (detailed design required to physically implement the work). Although the high level requirements remain unchanged, the manner in which they are realised is technology specific and thus the optimum presentation of Control Tables does reflect the technology of the interlocking system.