Sf.sub.6 circuit breaker having an incorporated capacitor

Abstract

A high tension circuit breaker includes a gastight cylindrical insulating case filled with SF.sub.6 gas or the like and defining for each phase at least one current interrupting chamber. A fixed main contact and a fixed arcing contact are fixedly mounted within the chamber. Moving equipment of the circuit breaker includes moving main and arcing contacts and a member for moving the moving main and arcing contacts towards and away from the fixed main contact and the fixed arcing contact. A cylinder is fixedly mounted in said chamber and supports internally a movable blast piston and terminates in a blast nozzle facing the fixed contacts. A capacitor is disposed inside the circuit interrupting chamber optionally with a parallel connected varistor. A mechanism in the form of a switch including a fixed and a movable contact operates to insert the capacitor and the parallel connected varistor temporarily during both closing and opening of the circuit breaker contacts. The capacitor is constituted by a stack of capacitor components disposed in a fixed insulating tube mounted within the chamber. A first end of the stack is electrically connected to a first current terminal of the circuit breaker, and a second end of the stack is electrically connected to an electrode fixed to a piece of the moving equipment and electrically connected to a second current terminal of the circuit breaker. The electrode may be a tube coaxial with the case and internally of the case.