A load-break switch has a housing holding insulation gas at ambient pressure; a first main contact and a second main contact being movable relative to each other in an axial direction of the switch; a first arcing contact and a second arcing contact being movable relative to each other in the axial direction and defining an arcing region where an arc is formed during a current breaking operation, wherein the arcing region is located radially inward from the first main contact; a pressurizing system pressurizing a quenching gas during the current breaking operation; and a nozzle system arranged to blow the pressurized quenching gas onto the arc. The first main contact includes at least one pressure release opening to allow gas flow in a radial outward direction. A total area of the pressure release opening suppresses a reduction of gas flow out of the pressure release opening.

A system including ruggedized optic fiber cable assembly for use with an arc detection relay to protect electrical components from faults resulting in an arc flash. The cable assembly includes a pair of ruggedized ST connectors located at opposite ends of a ruggedized optical fiber cable. The cable includes an optical fiber core surrounded by a transparent gel layer and a transparent jacket surrounding the gel layer. Each ST connector includes a boot formed of a resilient material to provide shock absorption for the portion of the optical fiber cable extending through it. An accessory electronic cable is also provided, as are couplers, adapters for mounting the couplers onto walls, and sleeves with air pockets to enhance the ruggedness of the cable at points of stress, e.g., bends.

A system including ruggedized optic fiber cable assembly for use with an arc detection relay to protect electrical components from faults resulting in an arc flash. The cable assembly includes a pair of ruggedized ST connectors located at opposite ends of a ruggedized optical fiber cable. The cable includes an optical fiber core surrounded by a transparent gel layer and a transparent jacket surrounding the gel layer. Each ST connector includes a boot formed of a resilient material to provide shock absorption for the portion of the optical fiber cable extending through it. An accessory electronic cable is also provided, as are couplers, adapters for mounting the couplers onto walls, and sleeves with air pockets to enhance the ruggedness of the cable at points of stress, e.g., bends.

Device, circuit, system, and method for arc suppression. A contact separation detector is configured to output an indication of a separation state of a pair of electrical contacts. A contact bypass circuit, coupled to the contact separation detector, is configured to provide an electrical bypass between the pair of contacts based on the indication.

A gas-insulated low- or medium-voltage load break switch includes: a housing defining a housing volume for holding an insulation gas at an ambient pressure; a first arcing contact and a second arcing contact arranged within the housing volume, the first and second arcing contacts being movable in relation to each other along an axis of the load break switch and defining a quenching region in which an arc is formed during a current breaking operation; a pressurizing system having a pressurizing chamber arranged within the housing volume for pressurizing a quenching gas from an ambient pressure p.sub.0 to a quenching pressure p.sub.quench during the current breaking operation; and a nozzle system arranged within the housing volume for blowing the pressurized quenching gas in a subsonic flow pattern from the pressurization chamber onto the arc formed in the quenching region during the current breaking operation. The nozzle system includes at least one nozzle arranged for blowing the quenching gas from an off-axis position predominantly radially inwardly onto the quenching region.

A system including ruggedized optic fiber cable assembly for use with an arc detection relay to protect electrical components from faults resulting in an arc flash. The cable assembly includes a pair of ruggedized ST connectors located at opposite ends of a ruggedized optical fiber cable. The cable includes an optical fiber core surrounded by a transparent gel layer and a transparent jacket surrounding the gel layer. Each ST connector includes a boot formed of a resilient material to provide shock absorption for the portion of the optical fiber cable extending through it. An accessory electronic cable is also provided, as are couplers, adapters for mounting the couplers onto walls, and sleeves with air pockets to enhance the ruggedness of the cable at points of stress, e.g., bends.

An automatic transfer switch (100) for automatically switching an electrical load between two power sources is provided. Two power cords (106) enter the ATS (A power and B power inputs) and one cord (109) exits the ATS (power out to the load). The ATS has indicators (107) located beneath a clear crenelated plastic lens (108) that also acts as the air inlets. The ATS (100) also has a communication portal (103) and a small push-button (104) used for inputting some local control commands directly to the ATS (100). The ATS (100) can be mounted on a DIN rail at a rack and avoids occupying rack shelves.

A residual load circuit breaker (1) includes a rotary switch body (23), which includes a contact blade (24, 25, 26, 27), that is rotatable about an axis (A) and is arranged between a feed line connection (20) and a discharge line connection (21), and includes end-side contact surfaces (28, 29, 30, 31) protruding in a radial direction. The contact surfaces, in a closed rotary position (S1) of the rotary switch body (23), are in touching contact with the feed line connection (20) and with the discharge line connection (21). In an open rotary position (S2) of the rotary switch body (23), the contact surfaces are each spaced with respect to the feed line connection (20) and with the discharge line connection (21). The residual load isolating switch (1) is rotationally limited in one rotational direction for performing switching movements and can be actuated unidirectionally and cyclically.

This disclosure relates generally to power isolation switch devices. In one embodiment, a power isolation switch device has a power insulator, an arc breaker, and a switch. The power insulator and the switch are connected in parallel. The arc contact is operably associated with the switch such that the arc contact is removed from the arc chute as the switch is opened and is inserted to contact the arc chute when the switch is closed. In this manner, the power isolation switch device does not need an interrupter and can be provided so as to be less bulky.

A gas-insulated low- or medium-voltage switch for system voltages within 1 to 52 kV and for up to 2000 A rated current includes first and second contacts being movable in relation to each other along an axis of the switch and defining a quenching region in which an arc is formed during a current breaking operation; and an arc-extinguishing system for extinguishing the arc during the current breaking operation. The arc-extinguishing system may include a pressurization system with a puffer chamber, and a nozzle system connecting the pressurization system with the quenching region, the nozzle system having a nozzle at its outlet for blowing the pressurized quenching gas onto the arc formed in the quenching region during the current breaking operation; and a swirling device configured for generating a subsonic swirl flow of a quenching gas onto the quenching region during the current breaking operation, wherein the swirling device is arranged at an entrance of the nozzle system. The arc-extinguishing system further includes a swirling device configured for generating a subsonic swirl flow of a quenching gas onto the quenching region during the current breaking operation, wherein the swirling device is arranged at an entrance of the nozzle system.