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controllers) are arranged along the route, e.g. in control cabinets. These clusters communicate
with each other via existing or new network infrastructures (open networks according to EN
50159-2, class 5). They are operated and maintained decentrally from a higher-level location.

Interfaces

Further essential features of the integration capability are the physical interface of the axle
counting technology to the superordinate system as well as its information content.

Relay Interface
In the course of development, the potential-free, safe relay interface has proven itself to date. The
focus was on integration into electromechanical, relay and electronic interlockings. The
information content usually comprises "free" / "occupied".

Software Interface

Compared to a relay interface, a crucial advantage of serial interfaces is the bidirectional
transmission of different information, such as direction, diagnostics and speed, via a single
connection. A connection to the already existing, secure communications within an interlocking
system must be possible. Therefore, the serial connection and the axle counting system's flexible
configuration open up a multitude of possibilities.
The centralised and decentralised arrangement and the interfaces, determine to a certain extent
the visual appearance and the mechanical integration of the axle counting components.

Axle Counter or Track Circuits – what is the best solution?

Minimum Installation Effort

Most of the track circuit variants in use nowadays require the installation of various components
in the track. In operation, these often proved to be susceptible to faults and extremely
maintenance-intensive. By reducing the number of track-side components, new types of train
detection systems – such as the ETCS or CBTC – aim to counteract these problems. However,
these approaches often require a vital fallback system that is globally done by modern axle
counter systems. Inductive wheel sensors and axle counters detect track vehicles regardless of
their equipment and origin. In addition, the use of robust and compact wheel sensors in
combination with smart system architectures enables the minimization of track-side components
– which significantly simplifies installation and maintenance.

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วิิศวิกรรมสาร ปีีที่่� 74 ฉบัับัที่่� 1 มกราคม-ม่นาคม 2564