Abstract: A differential protection device is designed for an electric disconnecting apparatus, the disconnecting apparatus comprising at least one fixed contact suitable for being connected to a corresponding electrical conductor, at least one movable contact, between a closed position, the movable contact being electrically connected to the corresponding fixed contact in the closed position and electrically isolated from the corresponding fixed contact in an open position, and an actuator for activating opening of the movable contacts when a differential fault is detected. The differential protection device comprises a controller for controlling the actuator. The differential protection device further comprises measuring circuitry for measuring an electrical variable associated with the controller and inhibiting circuitry for inhibiting the controller when the measured electrical variable satisfies a predetermined criterion.

Abstract: This differential protection device is designed for an electric disconnecting apparatus, the disconnecting apparatus comprising at least one fixed contact suitable for being connected to a corresponding electrical conductor, at least one movable contact, between a closed position, wherein it is electrically connected to the corresponding fixed contact, and an open position, wherein it is electrically isolated from the corresponding fixed contact, and an actuator for activating the opening of the movable contacts when a differential fault is detected. The differential protection device comprises a control member for controlling the actuator. The differential protection device further comprises measuring means for measuring an electrical variable associated with the control member and inhibiting means for inhibiting control member when the measured electrical variable satisfies a predetermined criterion.