Patent ID: 7898780

Claim:
An electronic differential switch connected to at least one phase cable and one neutral cable of an electric network, the electronic differential switch comprising: a second winding having first and second ends, the first end of the second winding being directly connected to one of the phase and neutral cables; a first winding associated with the second winding; at least one toroid associated with the first winding; a main switch connected to the phase and neutral cables; a driving relay for the main switch, the second winding being associated with the driving relay; a diode bridge; an integrated circuit for measuring a differential current flowing in the first winding and generating a driving signal, the first and second windings being coupled to one another through the integrated circuit and the diode bridge; and at least one transistor having a control terminal that is connected to an output of the integrated circuit so that the control terminal receives the driving signal from the integrated circuit, the driving signal controlling the at least one transistor so as to: in the absence of an alarm condition, turn on the at least one transistor, excite the driving relay, and close the main switch; or in the presence of the alarm condition, turn off the at least one transistor, release the driving relay, and open the main switch, wherein in case of failure of the integrated circuit, the at least one transistor is automatically maintained in the turn-off condition so that the main switch is automatically maintained in the open condition, so as to ensure safety of a downstream system to which the electronic differential switch is connected, and the at least one transistor is coupled to the second end of the second winding through the diode bridge.