Abstract: A high voltage self-blowing circuit breaker with closing resistors is equipped with an auxiliary contact inserted in the trip control circuit of an electrical circuit breaker. The auxiliary contact is actuated by the mechanical control rod of the circuit breaker, in such a way as to prevent any operator closing error. A high-speed mechanism is inserted in the link system connecting the control rod and the auxiliary contact, with a dead travel mechanism to delay closing of the auxiliary contact when a closing operation takes place and to prevent a tripping order, liable to cause a flashover on the inserter contacts and damage to the circuit breaker, from being transmitted too early.

Abstract: The operating rod 24 of a high-voltage puffer circuit-breaker is guided inside the support insulator 12 by insulator guides 40 mounted in the areas where the superimposed porcelain sections 14, 16 of the support insulator 12 join. A sealing O-ring 44 is inserted between the porcelain sections 14, 16 and circumferentially surrounds the edge 42 of the insulator guide 40 to center the latter.

Abstract: The column-shaped active part of a metal-clad circuit breaker is fastened at its upper part by stays to the metal tank. The stays show some elasticity, so as to exert a centering force on the column and oppose any excessive displacement when a shock or an earthquake occurs.