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.

The invention provides for an electronic functional device such as an isolator/barrier for input/output process connection to a plurality of field devices possibly operating in a hazardous environment, the functional device having mounted there-to a disconnect element, such as a knife disconnect element, so as to be associated therewith and to provide disconnect functionality between the field devices and the isolator/barrier device, the mounting of the disconnect element at the isolator/barrier device also serving to provide further indication of the field device associated with the disconnect element.

The invention provides for an electronic functional device such as an isolator/barrier for input/output process connection to a plurality of field devices possibly operating in a hazardous environment, the functional device having mounted there-to a disconnect element, such as a knife disconnect element, so as to be associated therewith and to provide disconnect functionality between the field devices and the isolator/barrier device, the mounting of the disconnect element at the isolator/barrier device also serving to provide further indication of the field device associated with the disconnect element.

A circuit breaker having a circuit operating device according to one embodiment of the present invention includes a circuit unit having a main circuit, a detecting unit having a detection circuit for detecting a fault current in the main circuit, and a circuit operating device configured to allow connection or isolation between the main circuit and the detection circuit, wherein the circuit operating device includes a first fixed unit and a second fixed unit connected to the main circuit and the detection circuit, respectively, and arranged in parallel to each other, and a moving unit rotatably coupled between the first fixed unit and the second fixed unit to connect or isolate the main circuit and the detection circuit to or from each other.

A circuit breaker having a circuit operating device according to one embodiment of the present invention includes a circuit unit having a main circuit, a detecting unit having a detection circuit for detecting a fault current in the main circuit, and a circuit operating device configured to allow connection or isolation between the main circuit and the detection circuit, wherein the circuit operating device includes a first fixed unit and a second fixed unit connected to the main circuit and the detection circuit, respectively, and arranged in parallel to each other, and a moving unit rotatably coupled between the first fixed unit and the second fixed unit to connect or isolate the main circuit and the detection circuit to or from each other.

An electric power distribution switch incorporates a stress-relieving connection structure, a closing guiding structure, a weather shield structure and a contact structure.

An electrical contact includes a knife having a first portion, a second portion, and a fixed contact. The fixed contact comprises a galvanic contact point and an arc ignition point. The knife is configured to operate in a first position, where the knife insulated from the fixed contact; a second position, wherein the closest distance between the knife and the fixed contact is between the first portion and the arc ignition point to form an electrical arc between the first portion of the knife and the arc ignition point; a third position, wherein the closest distance between the knife and the fixed contact is between the second portion of the knife and the galvanic contact point; and a fourth position, where the knife and the fixed contact are electrically coupled, namely the second portion of the knife and the galvanic contact point are electrically coupled.

An electrical contact includes a knife having a first portion, a second portion, and a fixed contact. The fixed contact comprises a galvanic contact point and an arc ignition point. The knife is configured to operate in a first position, where the knife insulated from the fixed contact; a second position, wherein the closest distance between the knife and the fixed contact is between the first portion and the arc ignition point to form an electrical arc between the first portion of the knife and the arc ignition point; a third position, wherein the closest distance between the knife and the fixed contact is between the second portion of the knife and the galvanic contact point; and a fourth position, where the knife and the fixed contact are electrically coupled, namely the second portion of the knife and the galvanic contact point are electrically coupled.

A surface layer including a base material made of a conductor and dispersed particles dispersed in the base material is formed on a surface of a fixed contact, and the dispersed particles each include a base particle that is metal oxide and a coating layer formed on an outer surface of the base particle.

A surface layer including a base material made of a conductor and dispersed particles dispersed in the base material is formed on a surface of a fixed contact, and the dispersed particles each include a base particle that is metal oxide and a coating layer formed on an outer surface of the base particle.