Modern signaling and information technology from Siemens Transportation Systems (TS) will ensure efficient operations from now on in the new RegioTram tunnel at the intersection of the tramway and railway at Kassel's main train station and culture forum – the "Kulturbahnhof". The newly built tunnel line which connects the city's previous tram network and DB's regional lines and was inaugurated on August 19 has been equipped by TS with intelligent control and safety systems. The order was placed by the local transit operator Kasseler Verkehrs-Gesellschaft AG (KVG).

The particular challenge in this project was how to make the transition from the DB system to the local tram network. First of all, both rail systems have different traction power supplies. Second, two interlocking generations and two different sets of operating codes collide here. Therefore, adjustments had to carried out both in the DB interlocking and in the KVG interlocking in order to ensure the safe passage of trains from one system to the other.

A Sicas type interlocking is now controlling the switches and signals inside the tunnel completely electronically and, together with an axle counting system, is monitoring all train and tram movements on this section. When a train enters the 170-meter tunnel, the interlocking automatically takes over the complete train protection tasks for the driver. It also ensures that the headways between the individual lines are observed – even in the case of more frequent service and irrespective of limited visibility conditions. In addition, the system creates more efficient procedures in the station area and optimizes travel times.

The interlocking itself is controlled from the KVG control center located in the Wilhelmshöhe maintenance depot, which was also expanded in the course of this project. The control center includes a modern Vicos operator control and display system by Siemens which registers and displays all movements on the line. It was already in operation before the new RegioTram tunnel was built, for prior to that it had monitored the Lossetalbahn line between Kassel and Hessisch-Lichtenau and the Kassel–Baunatal rail link. Interlocking equipment from Siemens is installed on both of these lines.

So far, the tunnel project at Kassel's main railway station marks the biggest infrastructure project ever realized in North Hesse. For the first time, a direct connection has been set up between the KVG tram network in the city and the DB regional rail services. It will enable future passengers from the outlying regions to take the RegioTram directly into downtown Kassel without having to change systems.