Abstract: At a connection portion between a common duct penetrating in an arrangement direction through switchgears arranged in the arrangement direction inside an electrical room, and an exhaust duct via which the common duct and outside of the electrical room communicate with each other, an end of the common duct is bent inward to form a first exhaust duct joining portion, and an end of the exhaust duct is bent outward to form a common duct joining portion. In a state in which an outer surface of the first exhaust duct joining portion and an inner surface of the common duct joining portion are in contact with each other, the first exhaust duct joining portion and the common duct joining portion are fastened and fixed by two or more pairs of bolts and welding nuts.

Abstract: A bus bar connecting device having a first bushing which has a first protruding part projecting to the outside of the first pressure vessel 4 and a first connection part, a second bushing which has a second protruding part projecting to the outside of the second pressure vessel and a second connection part, a connecting conductor part that electrically connects the first connection part and the second connection part, and an intermediate tank having a hand hole and a lid for sealing, wherein the intermediate tank stores the first protruding part and the second protruding part in an own internal space so as to seal the stored parts, thereby the bus bar connecting device that has good switchgear assembly and can improve a line unit workability is provided.

Abstract: A bus bar connecting device having a first bushing which has a first protruding part projecting to the outside of the first pressure vessel 4 and a first connection part, a second bushing which has a second protruding part projecting to the outside of the second pressure vessel and a second connection part, a connecting conductor part that electrically connects the first connection part and the second connection part, and an intermediate tank having a hand hole and a lid for sealing, wherein the intermediate tank stores the first protruding part and the second protruding part in an own internal space so as to seal the stored parts, thereby the bus bar connecting device that has good switchgear assembly and can improve a line unit workability is provided.

Abstract: At a connection portion between a common duct penetrating in an arrangement direction through switchgears arranged in the arrangement direction inside an electrical room, and an exhaust duct via which the common duct and outside of the electrical room communicate with each other, an end of the common duct is bent inward to form a first exhaust duct joining portion, and an end of the exhaust duct is bent outward to form a common duct joining portion. In a state in which an outer surface of the first exhaust duct joining portion and an inner surface of the common duct joining portion are in contact with each other, the first exhaust duct joining portion and the common duct joining portion are fastened and fixed by two or more pairs of bolts and welding nuts.

Abstract: An object is to eliminate, through an inexpensive structure, degradation in withstand voltage performance and degradation in energization performance caused by heating in a vacuum circuit breaker. The vacuum circuit breaker includes a main circuit structure body having an insulation rod, a vacuum valve, a movable side terminal, and the like and an insulating holder for supporting the main circuit structure body. The insulating holder is a frame structure body having opening portions in the top and bottom surfaces and both side surfaces of the section in which the vacuum valve is disposed and the section in which the insulation rod is disposed.

Abstract: An object is to eliminate, through an inexpensive structure, degradation in withstand voltage performance and degradation in energization performance caused by heating in a vacuum circuit breaker. The vacuum circuit breaker includes a main circuit structure body having an insulation rod, a vacuum valve, a movable side terminal, and the like and an insulating holder for supporting the main circuit structure body. The insulating holder is a frame structure body having opening portions in the top and bottom surfaces and both side surfaces of the section in which the vacuum valve is disposed and the section in which the insulation rod is disposed.