The present disclosure relates to a molded case circuit breaker, and particularly, to a molded case circuit breaker having an enhanced arc protecting function. The molded case circuit breaker includes: a power side terminal portion provided at a front side of an enclosure and having a fixed contact arm; a finger assembly coupled to the fixed contact arm, and disposed on a front surface of the power side terminal portion; and a base bus supporter coupled to an upper surface and a lower surface of the power side terminal portion, and having a finger hole through which the finger assembly is exposed. The base bus supporter is provided with a protection unit configured to enclose the finger assembly around the finger hole.

An arc chamber for a DC circuit breaker includes an entry side adapted to receive an electric arc, which was generated outside of the arc chamber and which propagates in a forward direction, a plurality of stacked splitter plates, and at least one inhibitor barrier. The at least one inhibitor barrier is arranged on the entry side to inhibit a reverse propagation of the electric arc out of the arc chamber in a reverse direction. DC circuit breaker comprising an arc chamber. Use of an arc chamber with a circuit breaker in a DC electrical system.

The present disclosure relates to an arc extinguishing device of a molded case circuit breaker which includes a fixed contactor fixedly provided on part of a base assembly case; a movable contactor brought into contact with or separated from the fixed contactor; and an arc extinguishing unit configured to extinguish an arc generated when the movable contactor is separated from the fixed contactor, and the arc extinguishing unit including a pair of side plates provided on the base assembly case; and a plurality of grids provided to have a predetermined distance between the pair of side plates, and the grid including a first grid formed with a first cutout portion on a first side surface where an arc is generated; and a second grid formed with a second cutout portion having a depth different from that of the first cutout portion on a second side surface where an arc is generated.

An extinguishing gas filtering device for an electric current switchgear with separable contacts, including an electric arc extinguishing chamber, includes, assembled together an inlet part for the extinguishing gases, made of a metal material and including an inlet aperture intended to be fluidically connected with an extinguishing gas outlet of the switchgear; an outlet aperture; a flared wall extending between the inlet and outlet apertures; a gas diffuser, which covers the outlet aperture, being planar in shape and including through-apertures; a filter made of porous metal foam, placed at the output of the gas diffuser.

A breaking device for interrupting current includes an electrically conducting outer member, an electrically conducting inner member arranged radially inside the outer member with respect to a breaking axis and an electrically insulating or semiconducting breaking member arranged radially between the outer member and the inner member with respect to the breaking axis, where the breaking member is arranged to move along the breaking axis from a starting position to a protruding position in which the breaking member protrudes from a space within the outer member for interrupting a current between the outer member and the inner member and the breaking member includes a first tubular including a first insulating material and a second insulating material, where the first insulating material has a higher wear resistance than the second insulating material.

An arc extinction apparatus according to an embodiment of the present disclosure comprises a chamber unit, a division unit, a filter unit, and a cover unit. A discharge port is formed in the chamber unit such that a fluid in the chamber unit is discharged to the outside. An insertion groove is provided on inner faces of the chamber unit that face each other. The division unit is coupled to the inside of the chamber unit. In addition, the division unit divides a path of the fluid discharged through the discharge port into multiple paths. The filter unit is disposed in the discharge port and filters out at least one predetermined material from the fluid passing through the discharge port. The cover unit comprises a plurality of exhaust pipes and is coupled to the discharge port from the outside of the filter unit.

An electromagnetic contactor is disclosed. An electromagnetic contactor according to an embodiment of the present disclosure includes an arc extinguishing unit. The air extinguishing unit is configured to surround a position where a fixed contactor and a movable contactor are in contact with each other. Accordingly, an arc generated between the fixed contactor and the movable contactor can extend toward a grid without arbitrarily flowing in an inner space of the electromagnetic contactor. Further included is an arc box unit according to an embodiment of the present disclosure. An arc outlet is formed passing through the arc box unit. An arc that is extinguished while passing through the grid can be discharged to the outside of the electromagnetic contactor through the arc outlet. Accordingly, the arc can be extinguished and discharged quickly and effectively. As a result, components of the electromagnetic contactor are not damaged by the generated arc.

A switch pole for a low voltage switching device including an insulating casing defining an internal space with a contact region and an arc extinguishing region of said switch pole, a fixed contact assembly and a movable contact assembly positioned in said contact region and including, respectively, one or more fixed contacts and one or more movable contacts, which can be mutually coupled or uncoupled, and an arc chamber positioned in said arc extinguishing region and including a plurality of parallel arc-breaking plates and a terminal arc-breaking element, which includes a plate portion arranged in parallel to said arc-breaking plates and a cover of electrically insulating material coating, at least partially, a surface of said plate portion.

A disconnect has a housing defining a cavity, a busbar fixed in the housing and extending through the cavity, a piston movable in the cavity past the piston for breaking a piece out of the busbar, and a plurality of metallic filter elements exposed in the cavity below the busbar and electrically connecting with the piece on activation of the disconnect. An igniter displaces the piston in the cavity into engagement with and past the busbar so as to break the piece out of busbar and displace it past the filter elements such that an arc created by breaking out the piece is drawn by the piece away from the busbar and energy of the arc heats and is dissipated in the filter elements.

A switch includes: a first stationary contact having a first stationary contact point; a second stationary contact having a second stationary contact point; a movable contact having a first movable contact, and a second movable contact point; a first magnet pair defined by magnets having surfaces facing each other, the magnets of the first magnet pair being disposed with the first stationary contact point and the first movable contact point therebetween in such a manner that the magnets of the first magnet pair become farther from each other outwardly; and a second magnet pair defined by magnets having surfaces facing each other, the magnets of the second magnet pair being disposed with the second stationary contact point and the second movable contact point therebetween in such a manner that the magnets of the second magnet pair become farther from each other outwardly.