Abstract: A switchgear includes an interrupter unit. The interrupter unit is provided with first and second switching contact pieces that are movable relative to one another. A switching-gas duct that runs through the interrupter unit originates at an arc gap in which an electric arc can burn. The duct connects the arc gap to the surroundings of the interrupter unit. At least some sections of the switching-gas duct are delimited by mutually encompassing elements similar to an annular duct. One of the elements is a first member which is braced at the end similar to a pipe joint and which has a free end that projects in the direction of the arc gap.

Abstract: A cooling device for hot gases occurring during and after a switching process in electrical installation equipment, preferably in low-voltage circuit breakers, includes a window, with narrow passage openings, arranged in the flow path of the hot switching gases, wherein the window is made from a material with high thermal conductivity and high heat capacity. The passage openings in the window are planar in shape and are arranged parallel to the flow direction of the switching gases such that no deflection of the switching gases takes place.

Abstract: In a switchgear cabinet, the line side power conductors upstream of the main breaker are surrounded with arc attenuating/extinguishing channels and protective conduit in a location prior to the conductor's attachment to the main breaker. Thus, passive arc attenuation can be had prior to the breakers, Personal Protection Equipment (PPE) levels can be predicted and controlled, and the need for action by circuit breakers during an arcing event is substantially lessened.

Abstract: Disclosed is a gas insulation circuit breaker with a structure for decreasing friction. The gas insulation circuit breaker comprises: a movable side supporting plate; a cylinder mounted so as to perform a reciprocating movement in a state that an outer surface thereof comes in contact with an inner surface of the movable side supporting plate; a contact spring for conduction disposed between the movable side supporting plate and the cylinder; and a movable arc contactor and a fixed arc contactor installed at the movable side supporting plate and the cylinder, respectively, and contacting and separated from each other by movement of the cylinder, wherein an end of the cylinder is tapered, and the outer surface of the cylinder comes in contact with the contact spring for conduction after a predetermined time lapses in a state that the cylinder has started to perform a closing operation during a circuit breaking operation.

Abstract: An arc chute assembly includes a housing having a lateral axis and a quenching portion disposed within the housing. The quenching portion includes at least two deion plates being spaced along the lateral axis of the housing and each having a cut portion wherein the cut portions are staggered along the lateral axis with respect to one another and are configured to mitigate an arc.

Abstract: A gas-blast circuit breaker is disclosed which includes a first contact and a second contact which can move relative to one another along a longitudinal axis. A blowout volume is arranged around the first contact. The blowout volume can be connected via a gas channel to an arc zone, in order to blow out an arc which is struck when the first contact is disconnected from the second contact. The blowout volume can be bounded radially on an outside by a separating element which separates the blowout volume from a low-pressure area. A flow opening, which allows a gas exchange, can lead in a radial direction from the low-pressure area into the blowout volume.

Abstract: The switching chamber is intended for a gas-insulated high-voltage circuit breaker. It contains an axially symmetrical housing and a contact arrangement held in the housing with two switching pieces, of which at least one is arranged such that it can move along the housing axis. The switching chamber housing has two hollow bodies consisting of electrically conductive material which can be connected to a high voltage and an insulating tube holding the hollow bodies axially at a distance. A separation zone, which is electrically shielded during operation of the circuit breaker, is formed in the surface of at least one of the two hollow bodies and separates two surface zones having different degrees of roughness from one another in the hollow body. In homogeneities in the surface of the switching chamber housing which may reduce the dielectric strength of the circuit breaker equipped with the switching chamber therefore do not have any effect.

Abstract: An arc chute assembly for a circuit breaker includes a plurality of U-type grids respectively including an engagement protrusion extended from each side thereof, the engagement protrusion having a key pin opening formed therethrough, a plurality of side walls respectively including a plurality of engagement slots formed therethrough, and a key pin inserted through corresponding ones of the key pin openings formed through the engagement protrusions which are inserted through the side walls and extended to an extent from an outer surface of each of the side walls. The apparatus employs the key pin for fixing the grids to the side walls, thereby facilitating assembly steps as well as decreasing an assembly time thereof.

Abstract: An arc stack for receiving a circuit breaker blade moveable between a closed position and an open position, includes a plurality of arc plates positioned substantially parallel to one another and arranged in a plurality of adjacent groups. Each of the groups includes one or more arc plates having substantially similar respective arc throats formed therein. The respective arc throats progressively decrease in size from group to group along the length of the arc stack in a direction extending away from the closed position of the blade. A connecting support maintains the plurality of arc plates substantially parallel to one another.

Abstract: An arc stack for receiving a circuit breaker blade moveable between a closed position and an open position, includes a plurality of generally rectangular are plates having substantially similar length and width dimensions and positioned substantially parallel to one another. The straight edges of the arc plates are in line with one another so that the are stack is generally rectangular in shape. The arc plates have respective arc throats formed therein having a plurality of sizes so as to form a longitudinal passageway extending through the arc throats following the arc generated by the blade moving between the closed and open positions. The arc plates include sets of arc plates with the arc plates in each set having identical arc throats. The sets of arc plates are arranged in order of decreasing arc throat size with the set having the largest arc throats being positioned adjacent the circuit breaker blade in the closed position.

Abstract: An arc quenching apparatus for circuit breakers includes a quenching space (10) in which each phase has a stationary contact (11) and a knife contact (12) pivotable in relation thereto, and which has a quenching chamber (13) in whose body member (15), made of an insulating material, quenching plates (14) are disposed in a spaced-apart relation so as to be located successively in relation to the path (P) of the opening movement of the knife contact (12). To overcome the problem of soot depositing in the quenching plate support structure made of an insulating material, which makes the support structure conductive between the quenching plates and adversely affecting the breaking capacity of the circuit breaker. Stop elements (20, 21a, 21b, 31, 42) are disposed between the ends of the quenching plates (14) on the knife contact (12) side and the body member (15).