Di-circuit breaker device and operating method for detecting a voltage on the pen conductor

A DI-circuit breaker device with a summation current converter for detecting fault currents in a phase conductor and a neutral conductor and with a detection device for detecting fault states of a protective ground conductor,

• wherein the detection device is connected on the input side to the phase conductor, the neutral conductor and the protective ground conductor and, on the output side, to a switching stage for controlling a DI-circuit breaker, wherein the DI-circuit breaker is adapted to switch switching contacts in the phase conductor, the neutral conductor and the protective ground conductor, wherein the detection device detects the presence of a phase voltage on the protective ground conductor as a fault state,
• wherein the detection device has a capacitive sensor which, when touched by a user, forms an electric capacitor with a capacitive reactance with respect to ground potential, wherein the detection device further has evaluating electronics which are adapted to determine a phase position by connecting the sensor to the phase conductor and, separately therefrom, to the neutral conductor, wherein the evaluating electronics determine the absence of a phase voltage on the protective ground conductor when it is established by the evaluating electronics that there is no voltage between the neutral conductor and the protective ground conductor.