Abstract: A switchgear according to the present invention includes: an air intake mechanism attachment body arranged on an air intake portion provided on a housing; an air intake opening provided in the air intake mechanism attachment body; a check valve type shutter which is arranged on the inner side of the air intake opening on the housing, performs an air intake from the outside of the housing, and blocks the air intake opening in the occurrence of an internal short circuit fault; and a ground fault partition body which is arranged between said check valve type shutter and a conductive portion in said housing and in which the length of at least one side is longer than said check valve type shutter.

Abstract: An insulation degradation monitoring device by which a degradation state of an insulator can be constantly monitored by a simple configuration, and a degradation degree can be decided. An insulation degradation monitoring device for an insulator, by which a high-voltage charging portion of an electric instrument is insulated from and supported to a grounding metal component, includes a penetration-type electric current sensor which is inserted to a connecting portion of the insulator and the grounding metal component, and detects a leakage electric current which is passed from the high-voltage charging portion through the insulator and is flowed to the grounding metal component; and a decision means which is connected to an output side of the electric current sensor, and decides a degradation degree of the insulator in accordance with a value of the leakage electric current.

Abstract: A current transformer support device includes three plate-like conductors, each of which has a first connection portion at one end and a second connection portion at the other end, and which are aligned linearly side by side while being spaced apart from one another, and a current transformer case which integrally insulates and supports the three conductors between the one end and the other end. The current transformer support device is characterized in that the current transformer case has current transformer attachment portions provided at positions corresponding to at least two of the three conductors, to which ring-like current transformer coils formed so as to insert the conductors are attached, and that the current transformer case and the current transformer coils attached to the current transformer attachment portions are formed into one unit with a hardening insulating material.

Abstract: An insulation degradation monitoring device by which a degradation state of an insulator can be constantly monitored by a simple configuration, and a degradation degree can be decided. An insulation degradation monitoring device for an insulator, by which a high-voltage charging portion of an electric instrument is insulated from and supported to a grounding metal component, includes a penetration-type electric current sensor which is inserted to a connecting portion of the insulator and the grounding metal component, and detects a leakage electric current which is passed from the high-voltage charging portion through the insulator and is flowed to the grounding metal component; and a decision means which is connected to an output side of the electric current sensor, and decides a degradation degree of the insulator in accordance with a value of the leakage electric current.

Abstract: A switchgear according to the present invention includes: an air intake mechanism attachment body arranged on an air intake portion provided on a housing; an air intake opening provided in the air intake mechanism attachment body; a check valve type shutter which is arranged on the inner side of the air intake opening on the housing, performs an air intake from the outside of the housing, and blocks the air intake opening in the occurrence of an internal short circuit fault; and a ground fault partition body which is arranged between said check valve type shutter and a conductive portion in said housing and in which the length of at least one side is longer than said check valve type shutter.

Abstract: A current transformer support device includes three plate-like conductors, each of which has a first connection portion at one end and a second connection portion at the other end, and which are aligned linearly side by side while being spaced apart from one another, and a current transformer case which integrally insulates and supports the three conductors between the one end and the other end. The current transformer support device is characterized in that the current transformer case has current transformer attachment portions provided at positions corresponding to at least two of the three conductors, to which ring-like current transformer coils formed so as to insert the conductors are attached, and that the current transformer case and the current transformer coils attached to the current transformer attachment portions are formed into one unit with a hardening insulating material.

Abstract: A bus is placed at the center of a housing. Breakers and cables forming branch circuits branching from the bus are placed at the upper and lower stages in the housing, being displaced in the right-left direction. Spaces formed between the side wall of the housing and the side walls of an upper-stage breaker compartment and an upper-stage cable compartment containing the upper-stage apparatuses are used as paths leading to the housing ceiling for a bus compartment, and a lower-stage breaker compartment and a lower-stage cable compartment containing the lower-stage apparatuses. The bus compartment and all the apparatus compartments each directly lead to a ceiling portion of the housing and have an opening portion. Pressure discharge plates are provided on the opening portions.

Abstract: A bus is placed at the center of a housing. Breakers and cables forming branch circuits branching from the bus are placed at the upper and lower stages in the housing, being displaced in the right-left direction. Spaces formed between the side wall of the housing and the side walls of an upper-stage breaker compartment and an upper-stage cable compartment containing the upper-stage apparatuses are used as paths leading to the housing ceiling for a bus compartment, and a lower-stage breaker compartment and a lower-stage cable compartment containing the lower-stage apparatuses. The bus compartment and all the apparatus compartments each directly lead to a ceiling portion of the housing and have an opening portion. Pressure discharge plates are provided on the opening portions.