A breaking device for interrupting current includes an electrically conducting outer member, an electrically conducting inner member arranged radially inside the outer member with respect to a breaking axis and an electrically insulating or semiconducting breaking member arranged radially between the outer member and the inner member with respect to the breaking axis, where the breaking member is arranged to move along the breaking axis from a starting position to a protruding position in which the breaking member protrudes from a space within the outer member for interrupting a current between the outer member and the inner member and the breaking member includes an inner tubular element and an outer tubular element, where the outer tubular element is joined to an outer surface of the inner tubular element thereby defining a recess between the outer tubular element and the inner tubular element.

A system including an arc flash sensor that detects an arc flash event and an arc flash mitigation device in communication with the sensor. The mitigation device includes a path of least resistance having a path input and a path output. The arc flash sensor is located downstream the output. The mitigation device includes an electro-mechanical switch between the input and the output and an actuator. The mitigation device also includes a bypass power switch device that includes a solid-state circuit interrupter and that conduct current between the input and the output in response to an open-circuit condition of the switch. A system controller is provided to generate a trigger to activate the actuator to generate the open-circuit condition of the switch, which causes the power switch device to interrupt a fault current associated with a fault event in response to detection of the arc flash event.

A circuit breaker includes a vacuum interrupter. The interrupter includes a first movable electrode to which a first contact is connected and a second movable electrode to which a second contact is connected. The interrupter is operable between an open state and a closed state. In the open state, the first contact and the second contact are separated by a contact gap distance. In the closed state, the first contact and the second contact touch each other. The circuit breaker includes an ultrafast actuator operatively connected to each of the first and second movable electrodes. The ultrafast actuator is configured to change the vacuum interrupter from the closed state to the open state by simultaneously moving the first contact in a first direction along a first distance portion of the contact gap, and the second contact in a second direction along a second distance portion of the contact gap.

A system including an arc flash sensor that detects an arc flash event and an arc flash mitigation device in communication with the sensor. The mitigation device includes a path of least resistance having a path input and a path output. The arc flash sensor is located downstream the output. The mitigation device includes an electro-mechanical switch between the input and the output and an actuator. The mitigation device also includes a bypass power switch device that includes a solid-state circuit interrupter and that conduct current between the input and the output in response to an open-circuit condition of the switch. A system controller is provided to generate a trigger to activate the actuator to generate the open-circuit condition of the switch, which causes the power switch device to interrupt a fault current associated with a fault event in response to detection of the arc flash event.

A device includes an electro-mechanical switching device having an open-circuit and closed-circuit conditions and a path of least resistance having a path input and a path output with the switching device between the input and the output. The device includes a bypass power switch device that comprises a solid-state circuit interrupter and that is configured to conduct current between the input and the output in response to an open-circuit condition of the switching device. The device includes a current sensor that is connected to the output and configured to detect a fault current event. The device includes an actuator that is coupled to the switching device and a controller that is configured to generate a trigger signal to activate the actuator to cause the open-circuit condition of the switching device and to interrupt the fault current event by the power switch device, based on the detected fault current event.

A device includes an electro-mechanical switching device having an open-circuit and closed-circuit conditions and a path of least resistance having a path input and a path output with the switching device between the input and the output. The device includes a bypass power switch device that comprises a solid-state circuit interrupter and that is configured to conduct current between the input and the output in response to an open-circuit condition of the switching device. The device includes a current sensor that is connected to the output and configured to detect a fault current event. The device includes an actuator that is coupled to the switching device and a controller that is configured to generate a trigger signal to activate the actuator to cause the open-circuit condition of the switching device and to interrupt the fault current event by the power switch device, based on the detected fault current event.

A closing spring assembly for an electrical switching device is provided. The closing spring assembly is configured to exert a closing force on a moving contact of the switching device. The closing force helps to maintain physical and electrical contact between the moving contact and an associated stationary contact, so that the moving and stationary contacts form a path for conducing electric current through the switching device. The closing spring assembly is configured so that the closing force remains constant or decreases as the moving contact is driven away from the stationary contact during switching of the current path away from the moving and stationary contacts.

An automatic transfer switch includes a first conduction bar selectively coupled with a first power source and a load conduction bar; a second conduction bar selectively coupled with a second power source and the load conduction bar; a first blade assembly electrically coupled to the first conduction bar; and a second blade assembly electrically coupled to the second conduction bar. The first blade assembly is electrically coupled to a first source conduction bar in a closed position, and a first electromagnetic force induced by a first current flowing through the first blade assembly and the first conduction bar repulses the first blade assembly. The second blade assembly is electrically coupled to a second source conduction bar in a closed position, and a second electromagnetic force induced by a second current flowing through the second blade assembly and the second conduction bar repulses the second blade assembly.

A system including an arc flash sensor that detects an arc flash event and an arc flash mitigation device in communication with the sensor. The mitigation device includes a path of least resistance having a path input and a path output. The arc flash sensor is located downstream the output. The mitigation device includes an electro-mechanical switch between the input and the output and an actuator. The mitigation device also includes a bypass power switch device that includes a solid-state circuit interrupter and that conduct current between the input and the output in response to an open-circuit condition of the switch. A system controller is provided to generate a trigger to activate the actuator to generate the open-circuit condition of the switch, which causes the power switch device to interrupt a fault current associated with a fault event in response to detection of the arc flash event.

A device includes an electro-mechanical switching device having an open-circuit and closed-circuit conditions and a path of least resistance having a path input and a path output with the switching device between the input and the output. The device includes a bypass power switch device that comprises a solid-state circuit interrupter and that is configured to conduct current between the input and the output in response to an open-circuit condition of the switching device. The device includes a current sensor that is connected to the output and configured to detect a fault current event. The device includes an actuator that is coupled to the switching device and a controller that is configured to generate a trigger signal to activate the actuator to cause the open-circuit condition of the switching device and to interrupt the fault current event by the power switch device, based on the detected fault current event.