Relation between pre-warning time and actual train velocity in automatic level crossing signalling systems at level crossings

Abstract

At level crossings equipped with automatic level crossing signalling devices (which are category B and C crossings in Poland), warning time depends on several factors including the length of what is referred to as the level crossing's danger zone for road vehicles, and the train velocity. These systems are designed by taking into consideration the maximum train velocity applicable to the given railway line, which is why a train running with a velocity that is lower than the maximum one, e.g. a freight train, produces pre-warning time excess. The pre-warning time excess affects the redundant prolongation of the time when the level crossing is closed for road vehicles. What has been proposed in the article is to reduce the pre-warning time excess by making the pre-warning time depended on the actual train velocity. It describes a structural concept of a solution which should first be implemented in automatic level crossing signalling systems. Owing to adequate assumptions, the concept of the pre-warning time excess reduction exerts no negative effect on safety at level crossings.