ABSTRACT
Selected level crossings are monitored remotely by signallers or other staff with CCTV cameras mounted adjacent to the track. This allows a number of sites to be controlled by a single operator at a dedicated workstation. The original specification for these CCTV systems was based around black and white images. The pictures sent to the level crossing operator are used to check whether the crossing is ‘clear’ before allowing the train to continue its approach. The existing displays used in signal boxes are black and white cathode ray tubes (CRT) which are getting increasingly less reliable and costly to maintain.
