Abstract: The circuit breaker-contactor includes a circuit breaker part with mechanical contacts and a contactor part with mechanical contacts connected in series. A solid-state switch is connected in parallel to the contacts of the contactor part. A control unit controls the solid-state switch and the contactor part, in such a way as to close the circuit when the potential difference passes zero by conduction or interrupting the solid-state switch. The mechanical contacts perform only current conduction by shunting the switch in normal operation. The contacts of the circuit breaker part have associated with them an arcing electrode and a shunt circuit disposed to draw the arc, as soon as the contacts open, and to shunt the solid-state switch and contactor part mechanical contacts assembly.