Electromechanical switching device of an electric power circuit

A switching device comprising:

• at least one main breaker together with an upstream section and a downstream section of a power electrical circuit positioned on either side of the main breaker, said main breaker being configured to occupy first and second states isolating or connecting the upstream and downstream sections,
• a spring,
• a control power supply together with an actuator configured to cause a change from the first state to the second state of the main breaker counter to a force generated by the spring when the actuator is powered by a control signal generated by the control power supply equal to a first level,
• the spring being arranged to cause a change from the second state to the first state of the main breaker when the actuator is not powered,
• the control power supply being configured so that the control signal is equal to the first level for a given first period of time counting from receipt of a first signal then to a second level, lower than the first level, to hold the main breaker in the second state for as long as the main breaker has to be held in the second state,
• the control power supply being configured so that the control signal applied to the actuator is equal to a third level higher than the second level, upon receiving a second signal, wherein the control signal is held at the third level for a given second period of time or for as long as current flowing in the main breaker exceeds a given operating threshold,
• wherein the switching device comprises at least one current sensor configured to transmit the second signal to the control power supply if the current flowing in the main breaker exceeds the given operating threshold, wherein the switching device comprises a re-armable protection system configured for interrupting the second signal after the second period of time,
• said re-armable protection system being configured so as to occupy a closed state in which the closed state lets the second signal pass when the latter has a value lower than the given triggering threshold, together with an open state in which the open state interrupts the second signal whenever the second signal has a value higher than or equal to the given triggering threshold for the given second period of time, said re-armable protection system returning to the closed state when the second signal is once again lower than the given triggering threshold.