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.

The present invention relates to an enclosed type electromagnetic switch having a status indication function, and more particularly, to and enclosed-type electromagnetic switch having a status indication function that can show the electromagnetic switch's status on an enclosure.

The present invention relates to an enclosed type electromagnetic switch having a status indication function, and more particularly, to and enclosed-type electromagnetic switch having a status indication function that can show the electromagnetic switch's status on an enclosure.

A double-contact switch has first and second tubular vacuum switching chambers; a stationary electrode, between the first and second vacuum switching chamber, having a first stationary contact protruding into the first chamber and a second stationary contact protruding into the second chamber; a first electrode, arranged in the first chamber, moveable axially therein, having a contact support region and sealed off from the first chamber exterior; a second electrode, arranged in the second chamber, moveable axially therein, having a contact support region and scaled off from the second chamber exterior; a first contact compression spring applying a first spring force to the first movable electrode so the first electrode contact presses onto the contact protruding into the first chamber; and a second contact compression spring applying a greater, second spring force to the second movable electrode so the second electrode contact presses onto the contact protruding into the second chamber.

A double-contact switch has first and second tubular vacuum switching chambers; a stationary electrode, between the first and second vacuum switching chamber, having a first stationary contact protruding into the first chamber and a second stationary contact protruding into the second chamber; a first electrode, arranged in the first chamber, moveable axially therein, having a contact support region and sealed off from the first chamber exterior; a second electrode, arranged in the second chamber, moveable axially therein, having a contact support region and scaled off from the second chamber exterior; a first contact compression spring applying a first spring force to the first movable electrode so the first electrode contact presses onto the contact protruding into the first chamber; and a second contact compression spring applying a greater, second spring force to the second movable electrode so the second electrode contact presses onto the contact protruding into the second chamber.

A two terminal arc suppressor for protecting switch, relay or contactor contacts and the like comprises a two terminal module adapted to be attached in parallel with the contacts to be protected and including a circuit for deriving an operating voltage upon the transitioning of the switch, relay or contactor contacts from a closed to an open disposition, the power being rectified arid the resulting DC signal used to trigger a power triac switch via an optoisolator circuit whereby arc suppression pulses are generated for short predetermined intervals only at a transition of the mechanical switch, relay or contactor contacts from an closed to an open transition and, again, at an open to a close transition during contact bounce conditions.

A two terminal arc suppressor for protecting switch, relay or contactor contacts and the like comprises a two terminal module adapted to be attached in parallel with the contacts to be protected and including a circuit for deriving an operating voltage upon the transitioning of the switch, relay or contactor contacts from a closed to an open disposition, the power being rectified arid the resulting DC signal used to trigger a power triac switch via an optoisolator circuit whereby arc suppression pulses are generated for short predetermined intervals only at a transition of the mechanical switch, relay or contactor contacts from an closed to an open transition and, again, at an open to a close transition during contact bounce conditions.

An electrical device assembly and method to attach an isolated single stud fuse assembly to an electrical device are disclosed. The electrical device assembly consists of multiple studs, one or more of which is replaced with the isolated single stud fuse. A conductive copper landing zone receives an electrically isolated steel stud. When the landing pad assembly is orbital riveted into a plastic housing of the electrical device, the stud is locked into the housing permanently. Electrical devices such as disconnect switches and power distribution modules, both of which include multiple studs, are good candidates for being adapted with the single stud fuse assembly.

One embodiment describes a three-phase electromechanical switching device, which includes three single-phase switching devices mechanically and electrically coupled in parallel with one another, each single-phase switching device including a direct current electromagnetic operator that in operation receives a direct current control signal for switching of the device, stationary contacts disposed in a respective device housing, and a movable assembly that in operation is displaced by energizing the operator and that include movable contacts that open and close, with the stationary contacts, a single current carrying path through the respective single-phase switching device; in which each of the single-phase switching devices receives control signals from control circuitry coupled to the operators of the respective single-phase switching devices to cause at least one of the single-phase switching devices to open or close the single current carrying path at a desired time coordinated with a current zero-crossing or a predicted current zero-crossing of a phase of three-phase power.

One embodiment describes a three-phase electromechanical switching device, which includes three single-phase switching devices mechanically and electrically coupled in parallel with one another, each single-phase switching device including a direct current electromagnetic operator that in operation receives a direct current control signal for switching of the device, stationary contacts disposed in a respective device housing, and a movable assembly that in operation is displaced by energizing the operator and that include movable contacts that open and close, with the stationary contacts, a single current carrying path through the respective single-phase switching device; in which each of the single-phase switching devices receives control signals from control circuitry coupled to the operators of the respective single-phase switching devices to cause at least one of the single-phase switching devices to open or close the single current carrying path at a desired time coordinated with a current zero-crossing or a predicted current zero-crossing of a phase of three-phase power.