In an electrification system, a device that allows, through the maneuver of the control organs of which it is provided, to open or establish the electrical continuity between the various sections in which the overhead electrification lines are divided; in the closed position it allows the passage of current from one section to the other of the line; in the open position it prevents the passage of current. It is operated after the circuit-breakers related to the section circuits are activated
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