Abstract: Disclosed are a circuit breaking unit and an air circuit breaker including the same. The present disclosure provides a circuit breaking unit, including: a fixed contact; a movable contact that is in contact with or spaced apart from the fixed contact; a fixed contact terminal having the fixed contact disposed at a lower end thereof and extending upward; a movable contact terminal on which the movable contact is disposed and configured such that the movable contact moves in a direction toward the fixed contact or in a direction away from the fixed contact; and a low runner disposed extending upward from the fixed contact, one end thereof coupled to the fixed contact terminal, and the other end thereof spaced apart from the fixed contact terminal, wherein a magnet unit or a U assembly is disposed between the low runner and the fixed contact terminal.

Abstract: A current transformer according to the present invention may comprise a magnetic core, a secondary coil, and a magnetic flux compensation member. A main circuit of an air circuit breaker penetrates the magnetic core. In addition, the secondary coil is arranged to be adjacent to the magnetic core, and a secondary current is induced through a current flowing in the main circuit. In addition, the secondary coil supplies the induced secondary current to a relay. The magnetic flux compensation member may be coupled to the magnetic core so as to correct magnetic flux of the secondary coil.

Abstract: The present disclosure relates to an arc extinguishing assembly, including side members which are spaced apart by a certain distance and disposed to face each other; an exhaust which is installed on an upper part of the side member; a plurality of grids which are installed between the side members and having both ends fixed to each of the side members; an arc guide having one end coupled to the side member and installed under the plurality of grids; and a magnet which is installed such that both ends are respectively coupled to the side members under the plurality of grids, and forms an electromagnetic force in a direction toward the grid, and a circuit breaker including the same.

Abstract: The present disclosure provides an entrance and exit position detection device for a power device. The entrance and exit position detection device for a power device comprises: a cradle which is open on one side and has an arrangement space formed therein; a power device body which may be in the arrangement space and has a guide plate formed on one side portion thereof; and a position detection part which linearly detects the displaced position of the power device body while the cradle enters and exits the arrangement space. Also, the present disclosure provides an entrance and exit monitoring system which has the above-described entrance and exit position detection device for the power device.

Abstract: Disclosed is an air circuit breaker. The air circuit breaker according to an embodiment of the present disclosure includes a CT magnet unit. The CT magnet unit is provided in the air circuit breaker to cover a movable contact point exposed to the outside. A CT magnet is provided inside a case that forms the outer shape of the CT magnet unit. The CT magnet independently forms a sub magnetic field or forms a main magnetic field together with an extinguishing magnet provided in an arc extinguishing unit. Due to the magnetic field formed by the CT magnet, an arc that is generated receives the application of an electromagnetic force directed toward the arc extinguishing unit. Accordingly, the generated arc can be quickly moved and extinguished.

Abstract: A current transformer according to the present invention may comprise a magnetic core, a secondary coil, and a magnetic flux compensation member. A main circuit of an air circuit breaker penetrates the magnetic core. In addition, the secondary coil is arranged to be adjacent to the magnetic core, and a secondary current is induced through a current flowing in the main circuit. In addition, the secondary coil supplies the induced secondary current to a relay. The magnetic flux compensation member may be coupled to the magnetic core so as to correct magnetic flux of the secondary coil.