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Case Studies

Wireless PROFINET/PROFIsafe controls Arlberg road tunnel ventilation




The 14 km long Arlberg road tunnel in Austria connects Austria´s state of Tyrol located in the east with Vorarlberg in the west. The tunnel is designed for 1800 vehicles per hour and equipped with 4 ventilation centers including two vertical shafts with a height of 736 and 273 m respectively. The tunnel has been opened to traffic already first in 1978; a major renovation and safety upgrade has been carried out from 2014 to 2017 to replace outdated equipment and to further improve safety standards. This included of course also the service and safety facilities in the two vertical ventilation shafts.



The two ventilation shafts open - at their upper ends - into two cavern stations which contain the intake and exhaust air fans along with control and safety-related installations including an elevator system for the service personnel to travel inside the shafts down to the ground. The old elevator systems with their cable-based control technology have been now replaced by a state-of-the-art solution (STB Control Systems, Austria) based on a S 7F controller and wireless PROFINET/PROFIsafe communication. Two Radio modules DATAEAGLE 4712 (Schildknecht AG) have been mounted at the upper elevator station and the roof of the passenger cabin respectively. These series 4XXX modules are designed to especially “speak and understand” PROFINET/PROFIsafe and use Bluetooth 2.1 with frequency hopping for wireless communication.   



It was a challenging application to design and realize a highly reliable wireless communication path over a distance of almost 800 m and under the harsh and very limited space conditions inside the ventilation shafts. However, the combination of S 7F controller, wireless PROFINET/PROFIsafe communication, DATAEAGLE radio modules and Bluetooth 2.1 radio technology successfully meets these conditions.

Besides this application, a reliable wireless, Ethernet-based communication (PROFINET is Ethernet!) is a general and key requirement for any successful solution in the context of IIoT or Industrie 4.0.

In this sense, the solution descibed above is very much future-proof!      


Schildknecht AG

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