A gas circuit breaker includes: a fixed arc contact disposed on an axis of motion, whose tip is directed to one side in a first direction that is parallel to the axis of motion; a movable arc contact that can reciprocate along the axis of motion between a position when in contact with the tip of the fixed arc contact and a position when separated from the tip of the fixed arc contact; and a first permanent magnet and a second permanent magnet as a permanent magnet whose magnetic poles are aligned in a second direction that is a direction perpendicular to the first direction. The fixed arc contact has a shape that is gradually widened in a direction away from the axis of motion from the tip toward another side in the first direction.

A gas circuit breaker includes: a fixed arc contact disposed on an axis of motion, whose tip is directed to one side in a first direction that is parallel to the axis of motion; a movable arc contact that can reciprocate along the axis of motion between a position when in contact with the tip of the fixed arc contact and a position when separated from the tip of the fixed arc contact; and a first permanent magnet and a second permanent magnet as a permanent magnet whose magnetic poles are aligned in a second direction that is a direction perpendicular to the first direction. The fixed arc contact has a shape that is gradually widened in a direction away from the axis of motion from the tip toward another side in the first direction.

In an embodiment a switching device includes at least one stationary contact in a switching chamber containing a gas comprising H.sub.2 and one movable contact in the switching chamber, wherein the switching chamber has a switching chamber wall and a switching chamber base, and wherein the switching chamber at least partially comprises a polymer material configured to release hydrogen when heated.

A DC circuit breaker according to various embodiments may comprise: a first terminal unit connected to a power source; and a second terminal unit connected to the first terminal unit and connected to a load, wherein the first terminal unit includes at least a pair of first terminals connected to each other in parallel and connected to the power source, and the second terminal unit includes at least a pair of second terminals corresponding respectively to the first terminals and connected to each other in parallel so as to be connected to the load.

A DC circuit breaker according to various embodiments may comprise: a first terminal unit connected to a power source; and a second terminal unit connected to the first terminal unit and connected to a load, wherein the first terminal unit includes at least a pair of first terminals connected to each other in parallel and connected to the power source, and the second terminal unit includes at least a pair of second terminals corresponding respectively to the first terminals and connected to each other in parallel so as to be connected to the load.

A circuit interrupter includes: a first fixed terminal including a first fixed contact; a movable contactor which is formed as a separate part from the first fixed terminal and includes a first movable contact; a holding unit configured to hold the movable contactor so that the first movable contact is connected to the first fixed contact; and a squib configured to generate gas by combustion. In the circuit interrupter, pressure of the gas generated by the squib causes movement of the movable contactor in a direction away from the first fixed terminal so that the first movable contact is separated from the first fixed contact.

A circuit breaker includes a switching unit for interrupting an electrical circuit. The switching unit has a stationary fixed contact and a moving contact to be moved relative to the fixed contact and to be switched from a closed position to an open position. A quenching device for quenching an arc when the contacts are opened includes a prechamber for guiding the arc from the contacts to a quenching chamber. The prechamber has two insulating side walls and a pair of arc guide rails situated therebetween. A ferromagnetic shaped part is disposed on each of the side walls, and a permanent magnet is disposed in the region of the fixed contact. The magnetic field of the permanent magnet guides the arc along one of the arc guide rails.

A compact disconnect device includes a magnetic arc deflection assembly including at least one set of stacked arc plates and at least one magnet disposed adjacent switchable contacts and establishing a magnetic field across the stacked arc plates. The magnetic arc deflection assembly facilitates reliable connection and disconnection of DC voltage circuitry well above 125 VDC with reduced arcing intensity and duration. The disconnect device may be a compact fusible disconnect switch device having dual sets of switch contacts in the same current path.

A circuit interrupting device is provided. In some configurations, the circuit interrupting device includes a base and an arc chamber assembly received within the base. The arc chamber assembly includes an arc chamber framework and a plurality of splitter plates received within the arc chamber framework. The arc chamber framework includes a first plurality of protrusions and a second plurality of protrusions that laterally extend in a direction toward one another. Adjacent pairs of the first plurality of protrusions and the second plurality of protrusions are arranged on opposing sides of each of the plurality of splitter plates.

A circuit interrupting device is provided. In some configurations, the circuit interrupting device includes a base and an arc chamber assembly received within the base. The arc chamber assembly includes an arc chamber framework and a plurality of splitter plates received within the arc chamber framework. The arc chamber framework includes a first plurality of protrusions and a second plurality of protrusions that laterally extend in a direction toward one another. Adjacent pairs of the first plurality of protrusions and the second plurality of protrusions are arranged on opposing sides of each of the plurality of splitter plates.