Abstract: Provided is a gas-insulated switchgear having a circuit breaker tank with a reduced size. The gas-insulated switchgear includes: a connection conductor connected to two or more power cables, for each phase, inside the circuit breaker tank; a solid-insulated bus placed outside the circuit breaker tank and connected to the connection conductor via a connection bushing; and an instrument current transformer attached to the solid-insulated bus.

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: Provided is a gas-insulated switchgear having a circuit breaker tank with a reduced size. The gas-insulated switchgear includes: a connection conductor connected to two or more power cables, for each phase, inside the circuit breaker tank; a solid-insulated bus placed outside the circuit breaker tank and connected to the connection conductor via a connection bushing; and an instrument current transformer attached to the solid-insulated bus.

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: In a switch in which one end portion of a blade is pivotally attached to a fixed contactor and another end portion of the blade is brought into pressure contact with a fixed contactor by rotational operation of the blade, at least one slit is provided in each of a conductive contact surface, with respect to the fixed contactor, of the one end portion of the blade and a conductive contact surface, with respect to the fixed contactor, of the other end portion of the blade, so as to divide each of the conductive contact surfaces, thereby achieving multi-point contact on each of the conductive contact surfaces, and a thickness of a contact-pressure spring fixing portion of the blade at which a contact-pressure spring for bringing the other end portion into pressure contact with the fixed contactor is made smaller than that of the other end portion.

Abstract: To obtain a gas insulated switchgear which enables an improvement in maintainability. The gas insulated switchgear is characterized by including a main circuit device disposed inside a container in which an insulating gas is hermetically sealed; an operating mechanism disposed outside the container; a hermetic connecting shaft which transmits the drive force of the operating mechanism to the main circuit device; a first hermetic sealing portion disposed around the hermetic connecting shaft; and a second hermetic sealing portion which, having thereinside a hermetic sealing member, is disposed around the hermetic connecting shaft so as to be superimposed on the first hermetic sealing portion and also is provide in the atmosphere outside the container.

Abstract: A vacuum circuit breaker capable of efficiently dissipating heat generated in a vacuum valve includes a movable side contact and a fixed side contact which are arranged in the inside of the vacuum valve; a fixed side energization shaft to which the fixed side contact is fixed; a movable side energization shaft to which the movable side contact is fixed; an energization connection portion provided at a position where the movable side energization shaft protrudes from the vacuum valve; and a coupling body provided at the outside tip portion of the movable side energization shaft. The coupling body at the outside tip portion of the movable side energization shaft is coupled to an insulation operating rod.

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: In a switch in which one end portion of a blade is pivotally attached to a fixed contactor and another end portion of the blade is brought into pressure contact with a fixed contactor by rotational operation of the blade, at least one slit is provided in each of a conductive contact surface, with respect to the fixed contactor, of the one end portion of the blade and a conductive contact surface, with respect to the fixed contactor, of the other end portion of the blade, so as to divide each of the conductive contact surfaces, thereby achieving multi-point contact on each of the conductive contact surfaces, and a thickness of a contact-pressure spring fixing portion of the blade at which a contact-pressure spring for bringing the other end portion into pressure contact with the fixed contactor is made smaller than that of the other end portion.

Abstract: Provided is a gas-insulated switchgear that facilitates additional installation work and achieves reduction in working time in the case of increasing arranged boards in additional installation of open/close devices. A bus tank storing a bus is provided above a circuit breaker tank storing a circuit breaker, the bus is connected to a bus connection bushing provided at a width-direction end of the bus tank, a tank width dimension of the bus tank is smaller than an enclosure width dimension of the gas-insulated switchgear, and a space formed by a difference between the enclosure width dimension and the tank width dimension serves as a connection space for the bus when the gas-insulated switchgear is arranged in a row.

Abstract: A switchgear according to the present invention includes a disconnecting unit that includes multiple switches to switch electrical paths by rotation of blades, and a switch housing having a view port, and including the switches arranged therein, wherein planes of rotation of the blades and an arrangement direction of the switches intersect, and the switches are arranged rearward from the view port.

Abstract: A switch includes: switch blades for multiple phases which perform three-position switching among ON, OFF, and ground, using a rotation shaft; and phase-to-phase connection mechanisms which support the switch blades for the phases so as to be insulated among the phases and against the ground, and which connect the switch blades for the phases and cause them to cooperate with each other. The phase-to-phase connection mechanisms include fitting couplings made of an insulating material and each composed of a large-diameter endless frame body and a small-diameter endless frame body which are fitted to each other. The fitting couplings are arranged on the same axial line.

Abstract: A vacuum circuit breaker capable of efficiently dissipating heat generated in a vacuum valve includes a movable side contact and a fixed side contact which are arranged in the inside of the vacuum valve; a fixed side energization shaft to which the fixed side contact is fixed; a movable side energization shaft to which the movable side contact is fixed; an energization connection portion provided at a position where the movable side energization shaft protrudes from the vacuum valve; and a coupling body provided at the outside tip portion of the movable side energization shaft. The coupling body at the outside tip portion of the movable side energization shaft is coupled to an insulation operating rod.

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: A switch includes: switch blades for multiple phases which perform three-position switching among ON, OFF, and ground, using a rotation shaft; and phase-to-phase connection mechanisms which support the switch blades for the phases so as to be insulated among the phases and against the ground, and which connect the switch blades for the phases and cause them to cooperate with each other. The phase-to-phase connection mechanisms include fitting couplings made of an insulating material and each composed of a large-diameter endless frame body and a small-diameter endless frame body which are fitted to each other. The fitting couplings are arranged on the same axial line.

Abstract: A bus bar connection device for a switchgear has a first bushing with an internal stem conductor whose end is a first connection surface at a nose of the bushing. The bus bar connection device has a second bushing with an internal stem conductor whose end is a second connection surface at a nose of the bushing. The first connection surface of the first bushing is placed opposite the second connection surface of the second bushing, the axis of the first bushing being identical to the axis of the second bushing. A connection element electrically connects the first connection surface with the second connection surface. A cylindrical insulation adapter surrounds the nose of the first bushing, the nose of the second bushing, and the connection element as one.

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: A switchgear according to the present invention includes a disconnecting unit that includes multiple switches to switch electrical paths by rotation of blades, and a switch housing having a view port, and including the switches arranged therein, wherein planes of rotation of the blades and an arrangement direction of the switches intersect, and the switches are arranged rearward from the view port.

Abstract: A vacuum monitoring device of a vacuum circuit breaker with a line of a vacuum valve led out to the external of a metal tank through a bushing having a shield working as a low-pass filter, includes: a first antenna; a second antenna; a first and a second detection portion measuring intensity of an electromagnetic wave detected by the antennas; and a determination portion determining a vacuum deterioration of the circuit breaker by comparing the intensity of the electromagnetic wave detected by the first and the second detection portions, wherein the first and second detection portion include frequency filters passing a frequency band, of electromagnetic waves resulting from discharges occurring when the vacuum valve deteriorates in vacuum, which is attenuated by the shield.