Method to identify stray current hazards

The method for detection of danger from stray currents arising from railway lines with a direct current supply and an earth return rail. According to the method the voltage between the rails of the railway line, which act as the electricity return path, and earth is measured at a number of points along the railway line and transferred to a central evaluation point, where the measured values are compared with a reference value. An independent claim is made for a second method for detecting stray currents in which a short circuit switch is used to generate a second parallel path for return of the supply current. The current amplitude in the parallel path is measured and if it differs from a reference value a stray current is indicated and corresponding increased danger.