German Rail (DB AG) has given Siemens Transportation Systems (TS) the order to upgrade the main interlocking at Frankfurt. TS is to install an electronic interlocking at this vital railroad junction and integrate it into the local operations control center. Frankfurt is the site of one of seven operations control centers which will be in charge of monitoring, dispatching and controlling the entire railway traffic in German Rail’s mainline and regional system. The order is worth more than €47 million and includes, among other things, the rehabilitation of 315 signals, 331 switches, 41 electronically decentralized switches, and 306 track vacancy detection sections.

The type El S modular-design interlocking features Simis type computers. Simis stands for “fail-safe microcomputer system from Siemens”. Simis-type interlocking systems are already established world-wide and proven by many yeras of service. There are currently over 3000 Simis computers in operation world-wide. These systems operate with at least two microcomputers which, although identically structured and identically programmed, are completely independent of each other. This configuration guarantees utmost safety and availability of the system.

The main station in Frankfurt is a central junction for regional, as well as for interregional and international rail traffic. Every day 700 trains, 1,000 commuter trains and 350,000 passengers pass through this station, making it one of the busiest in Germany. The present interlocking at Frankfurt has been in service for over 40 years and is no longer suitable for implementing the changes planned for the geographical circuit in order to increase capacity. Siemens TS will start this upgrading work at the beginning of 2002, with the new systems due to go into operation in four phases during 2005.