In cooperation with Telma AG, Enotrac has developed the Interference Current Monitor (ICM); a protective device that monitors the primary current of a railway vehicle for potentially dangerous interference current frequencies. If these interference currents exceed the specified limits for more than the permissible time, the ICM opens a relay contact with which, for example, the main switch of the vehicle can be opened.

Installation of the ICM on a traction unit simplifies the formal verification of the compatibility of the vehicles with the track circuits of the respective infrastructure managers. The safety requirements of the ICM have been proven with FMEA and quantitative fault tree analysis.