Axle Counter

An axle counter is a railway train-detection system used to establish the occupancy status of a defined track section.

Detection points installed at the boundaries of the section detect and count the axles of passing trains. When a train enters the section, its axles are counted in. At the exit, the axles are counted out.

If the number of axles counted entering and leaving corresponds correctly, the system can determine that the section is clear. If the counts do not balance, the section remains indicated as occupied or otherwise requires the appropriate safety procedure before being restored.

Axle counters are widely used as an alternative to track circuits for train detection and can be particularly advantageous where track-circuit performance may be affected by ballast conditions, electrical interference or other infrastructure characteristics.

They are commonly integrated with railway interlocking, signalling, level-crossing and train-control systems.