Author:  Simon Reich, Thomas Bessoir

Sponsoring Agency:  U.S. Department of Transportation, Federal Railroad Administration, Office of Research and Development

Performing Agency:  Thomas K. Dyer, Inc.; Foster-Miller, Inc.

Date of Publication:  May 1993

Abstract:

This study has been conducted with the goal of gaining an insight into the issues of maintaining vital signal systems implemented with microprocessor chips and of making field changes to the application of such systems. To relate these abstract topics to concrete issues, two actual commercial systems were investigated, namely the General Railway Signal Company VPI® Vital Processor Interlocking and the GRS GENRAKODE™ microprocessor-based coded track circuit system.

One of the purposes of this study is to determine what actions should be taken by railroads to maintain signal-system safety when microprocessor-based signal systems receive maintenance to correct a failure and when such signal systems are modified after installation because of application changes such as a revision to the track plan or the signal aspects.

A second purpose of this study is to determine whether revisions are required to the Rules, Standards and Instructions Governing the Installation, Inspection, Maintenance and Repair of Signal and Train Control Systems, Devices, and Appliances (RS&I) due to the introduction of microprocessor-based signal systems and to suggest such revisions if they are indicated. These revisions, if any, would be based on the recommendations for maintenance and field-change procedures identified in the first part of the study.
 

No. of Pages:  51