PROBLEMS AND FINDINGS IN PERFORMING A SAFETY TEST

The idea of equipping railway signalling cabins with electronics has long been in the minds of engineers. It was conceved when it was realized that electronic elements could fully take over the functions of mechanical contacts. However, until the mid-1970's the electronics then available could not complete economically with the relay in signal cabins, and it was only with the introduction of the microcomputer that electronics became really interesting here. Microcomputers for railway signalling must meet very high safety requirements so that in the event of a failure no dangerous situation can arise. In the failed condition they must therefore have an operation-stopping effect. The is ensured in the investigated safe microcomputer system by, among other things, special output signal converters which allow the signals to pass only if two independent microcomputers processing them are in full agreement. In the event of a fault, a comparator device stops the processing cycle so that the converter outputs become dead. The operation-stopping side is linked to this condition.

  • Corporate Authors:

    Hestra Verlag

    Holzhofallee 33, Postfach 4244
    6100 Darmstadt 1,   Germany 
  • Authors:
    • BRANDL, H
  • Publication Date: 1983-11

Language

  • German

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00382631
  • Record Type: Publication
  • Source Agency: British Railways
  • Files: TRIS
  • Created Date: Apr 30 1984 12:00AM