Audio Frequency Track Circuit

Audio Frequency Track Circuits (AFTC) are used to detect the presence of a train on a track. They are designed to monitor long track lengths on jointless rails.HBLRAIL has developed an Audio Frequency Track Circuit based on RDSO specifications and is suitable for use even in AC or DC electrified areas where high levels of electromagnetic interference are encountered. The system is also designed to handle interference from traction return currents in electrified sections.The HBL AFTC equipment is compact and can be housed in a cabin up to 6 kilometers from the sensing point. The HBLRAIL AFTC system is bit coded and is designed to work sequentially and in point zones. The equipment can be supplied in 3 basic modes: Centre-fed, End-fed and Point zones, depending on the application.