23-07-2010, 08:31 AM
Firstly, define what you mean by points. The signalling scope for points is generally reasonably well defined in the UK but differs across countries and even infrastructure owners!
Care is needed when stating what constitutes a failure. For example, a detection switch can gradually drift out of tolerance and for the operator, that is a failure. However, for signalling, it is a design feature and the system is working correctly. In reverse, the frog could fracture but the signalling system wouldn't indicate the mechanical failure, the operator may not detect it either but the PWay techs would classify it as a failure.
Jerry
Care is needed when stating what constitutes a failure. For example, a detection switch can gradually drift out of tolerance and for the operator, that is a failure. However, for signalling, it is a design feature and the system is working correctly. In reverse, the frog could fracture but the signalling system wouldn't indicate the mechanical failure, the operator may not detect it either but the PWay techs would classify it as a failure.
Jerry
Le coureur