Abstract: In a metal encapsulated, pressurized gas insulated high voltage disconnect switch operating at voltages above 245 kV, weak arcs drawn during the switching operation are prevented from wandering off, so that they cannot commutate to the encapsulation and produce an arc to ground, by an electric field in the switching gap controlled by moving a field electrode jointly with the switching rod, with the motion cycles of the switching rod and the field electrode controlled during the closing and opening process in a forced manner by a lever linkage provided with steering rods for the switching rod and the field electrode.

Abstract: A disconnect switch for high-voltage installations is disclosed. The switch includes a pair of hollow contacts, one of which is movable, disposed in a grounded metallic housing filled with compressed gas. A spring-loaded contact-breaking pin is provided in one of the hollow contacts. The pin is provided at its free end with a recess which is engaged in the "on" position of the switch by a ratchet device pivotally disposed in the other contact. During movement of the movable contact toward the "off" position of the switch, the contact-breaking pin remains in contact with the ratchet device. The mechanically controlled ratchet device releases the contact-breaking pin at a given position of the movable contact. The contact-breaking pin is then returned by its spring into its hollow contact with a velocity greater than that of the movable contact.