Failsafe signalling system for automatic points operation - uses track-side detectors to interrogate stored commands in locomotive at critical locations

摘要

The fail-safe signalling system for automatic points operation consists of a number of track-side detectors (FR) and transmitters (SR) placed in advance of points (W1-4) and connected to a central signal box (ZE). At the start of the controlled section, an additional transponder (SGO) passes data to a passing locomotive containing coded identification signals for the points to be traversed along the selected route. To ensure that the programmed commands have been correctly stored in the locomotive's register, these points-safe signals are interrogated at each position within a safe stopping distance prior to each points installation. If coincidence is not detected, then an emergency braking sequence is initiated in the locomotive control circuits.