Abstract: Fault detection system (800) for a medium voltage circuit comprising assemblies of an electric power distribution cable (205), a first transformation center (210) comprising a first transformer and a first grounding conductor (603), a first grounding system comprising a first grounding resistor (RPAT1) connected to the first transformer through the first grounding conductor (603), the first transformation center (210) connected to a first end of the cable (205) and a second transformation center (220) comprising a second transformer and a second grounding conductor (603), a second grounding system comprising a second grounding resistor (RPAT2) connected to the second transformer through the second grounding conductor (603), the second transformation center (220) connected to a second end of the cable (205).

Abstract: The invention relates to a device for the measurement of an external electrostatic field, for example, for the detection of storms, which includes a first conductive element (1); an amplifier (2)in charge configuration; an electronic control device (3) which has an input (3a) connectable to the output (2b) of the amplifier (2), to receive an output signal (Vs); and a second conductive element (4) located near to the first conductive element (1) to subject it to a compensating electrostatic field created by a compensating signal (Vc) calculated and generated by the electronic control device, to avoid a drift in the output signal (Vs) caused by the integrating character of the configuration of the amplifier. The invention also relates to a system for differential measurement, a system and method for the detection of storms.