Siemens Mobility Lineside Electronic Unit S21

Trainguard® Lineside Electronic Unit S21 (LEU S21)

Full interoperability for European railways

Trainguard LEU S21

The Trainguard LEU S21 (Lineside Electronic Unit) forms the link between the existing fixed signals and the ETCS (European Train Control System) components in the track, the Eurobalises and Euroloops.

The telegrams are transmitted intermittently by means of Trainguard Eurobalises and, if required, semicontinuously by the Trainguard Euroloop. The indicated signal aspect is extracted by the LEU S21 and the associated telegram is selected and continuously transmitted as a serial data stream via a standardized interface to the transparent balise(s) or Euroloop modem. If a train fitted with ETCS equipment traverses the transparent balise(s) or Euroloop, the telegram is transmitted to the train and evaluated by the European Vital Computer (EVC, onboard computer).

Thanks to an identical telegram structure, the LEU S21 can control both Eurobalises and Euroloops; additional data configuration is thus not necessary. A conventional balise/loop antenna is sufficient on the train. 

Siemens Mobility ETCS LEU Lineside Electronic Unit
Switchgear cabinet with installed Trainguard LEU S21 MS und ELM S21 F (left) as well as an illustration of Trainguard LEU S21 MT (right)

Benefits

  • Compliance with all relevant European standards 
  • Modular design
  • Accommodation in concrete equipment houses, switchgear cabinets or relay rooms
  • High-reliability data transmission
  • No maintenance required
  • High level of availability
  • Low purchase and life-cycle costs
  • Low power consumption

Technical data – Trainguard LEU S21