A medium voltage load break switch includes a main contact and a knife. The knife is rotatable about a pivot point to connect to and be in contact with the main contact and to rotate about the pivot point to disconnect from and be spaced from the main contact. The load break switch also comprises a vacuum interrupter that has a fixed contact and a moveable contact. A lever rotates about a rotation point and a shaft of the moveable contact is aligned along an axis of the vacuum interrupter, and the shaft of the moveable contact is linked to the lever.

A disconnector for use in a switchgear structured to electrically connect between a power source and a load includes a pair of disconnector blades spaced apart by a distance and having a first end structured to selectively receive and form an electrical connection with a busbar contact and a second end structured to electrically couple to the load, and a pair of magnetic plates mechanically connected to inner surfaces of the pair of disconnector blades and structured to bias the pair of disconnector blades toward each other.

A current-interrupter device (1) comprising a circuit breaker (2) including a first stationary conductive support (4) carrying both a stationary arcing contact (14) and a movable arcing contact (16), and also carrying a movable permanent contact (17), the movable arcing contact (16) and the movable permanent contact (17) being electrically connected to the first stationary support (4), and a disconnector (3) including a second stationary conductive support (6) carrying a disconnector contact (18), and wherein: the movable disconnector contact (18) is in contact with the stationary arcing contact (14) when it is closed and spaced apart from the stationary arcing contact (14) when it is open; and the movable disconnector contact (18) and the movable permanent contact (17) are connected to each other when they are both in the closed position, and they are spaced apart from each other when one or the other is open.

A circuit breaker/disconnector apparatus for use in a power delivery system comprises a unidirectional DC circuit breaker which has a first terminal and a second terminal and is configured to automatically open during an overcurrent condition in a forward direction and to remain closed independent of current level in a reverse direction. A disconnector switch is in series with the circuit breaker. The disconnector switch has a first terminal for connecting to a first polarity connector of a power supply, a second terminal for connecting to a second polarity connector of the power supply and a common terminal connected to the first terminal of the circuit breaker. The disconnector switch has at least a first position in which the first terminal is connected to the common terminal and a second position in which the second terminal is connected to the common terminal. The second polarity connector of the power supply may be coupled to a track of a transport system and the second polarity connector of the power supply may be coupled to a live overhead cable or live third rail of a transport system. The apparatus can be used to safely ground the live cable or third rail when in a maintenance condition.

A three-position vacuum switch for realizing external grounding of a load side by using a bridge switch overcomes the problems in the prior art that load side grounding is realized depending on the opening and closing of a vacuum arc extinguishing chamber, a misoperation easily occurs because an operator cannot see the grounding situation intuitively, and when an operating mechanism machine has a problem, it needs to have a grounding line plugged in externally, which cause inconvenient operations with huge safety risks, a complicated structure and relatively high cost, characterized in that a bridge grounding switch is provided on the other side of the three-position vacuum switch to realize external grounding of the load side via the bridge grounding switch.

A “five-prevention” interlocking pole type high-voltage switchgear includes a pole bracket, embedded poles, and spring and earthing isolated switch operating mechanisms; every three poles are arranged in a row on the bracket, the spring operating mechanism is joined with the switch operating mechanism through the chamber door interlocking piece and mechanism interlocking piece; the chamber interlocking piece, mechanism interlocking piece and door lock plate are joined, the door lock plate is opposite the opening semi-axis pinch plate in the spring operating mechanism and the door lock plate is set with a door lock pin. Chamber interlocking piece movement is used to open or close the switch operating mechanism crank operation hole and corresponds to the start of close brake operation and limit brake of opening pinch plate in the spring operating mechanism and the limiting and opening of the opening semi-axis and cable chamber door in the spring operating mechanism.

Devices, methods and techniques are disclosed to interrupt a fault current in a high-voltage direct-current circuit. In one example aspect, a device includes a mechanical switch including a pair of contacts configured to be positioned apart upon activation of the circuit breaker, and a photoconductive component connected in parallel with the mechanical switch. The photoconductive component is configured to establish a current upon activation of the circuit breaker. The photoconductive component comprises a crystalline material positioned to receive a pulsed light signal from a laser light source, and a pair of electrodes coupled to the crystalline material and configured to allow an electric field to be established across the crystalline material to generate the current.

A multi-circuit DC breaking system is proposed. According to an exemplary embodiment of the present technique, there may be an advantage that by combining current-limiting technology and multi-circuit breaking technology, a failure may be quickly detected, a magnitude of a fault current may be firstly limited, and a breaking operation is performed, in a range of various fault currents, by distributing the fault currents to some circuits of multi-circuits configured in parallel, thereby easily increasing the capacity thereof.

A switchgear system operable at voltages up to 27 kV includes an enclosure containing atmospheric air and a loadbreak module disposed within the enclosure. The loadbreak module includes a loadbreak module housing made of a solid dielectric material, a vacuum interrupter enclosed within the loadbreak module housing and having a fixed contact and a movable contact, and an interchange electrically connected to the movable contact. The vacuum interrupter is operable to selectively break or establish an electrical pathway between the interchange and a terminal in response to movement of the movable contact relative to the fixed contact. The switchgear system further includes a bushing coupled to the enclosure and a disconnect switch electrically connected in series between the loadbreak module and the bushing. The disconnect switch includes a disconnect switch housing made of a solid dielectric material.

An arrangement and a method for switching high currents include at least one vacuum switching path and at least one rated-current contact switching path. The at least two switching paths are electrically connected in parallel. One current path for a rated current is routed over at least one rated-current contact of said rated-current contact switching path, and a parallel current path for a short-circuit current is routed over at least one contact of a vacuum tube of the vacuum switching path.