The line power and neutral conductors for an arc fault sensing circuit interrupter such as in a miniature circuit breaker are arranged as a rigid conductor surrounding and holding an insulated flexible conductor when passing through the Ground Fault Interrupter current transformer. Voltage metering takes place across the rigid conductor to enable arc fault detection and ground fault detection in the miniature circuit breaker within the space of a single current transformer.

An embodiment of the invention relates to a method for ground fault detection for low-voltage three-phase AC circuits having a neutral conductor, in which first to fourth analog current signals of the first to third phase conductors and of the neutral conductor of the three-phase AC circuit are ascertained that each contain the level or an equivalent of the level of the current. The analog current signals are time-division multiplexed, subjected to a/d conversion, and a sequence of time-division-multiplexed first to fourth digital current values present in first to fourth successive time frames form first to fourth current signals. Three of the four digital current signals are interpolated to ascertain interpolated current values. The current value of the time frame of the uninterpolated current signal and the interpolated current values for the time frame of the uninterpolated current signal are used for discovering the ground fault.

A plug-in summation current transformer module for insertion into a module-overlapping installation space of a multi-pole rail-mounted device that is formed of a plurality of housing modules has a summation current transformer and primary conductors routed through the tubular summation current transformer. The primary conductors have primary conductor ends. A primary conductor holder for fixing the primary conductor ends is fastened to the summation current transformer and adopts a fixing position for holding the primary conductor ends in an assembling position for insertion into a module-overlapping installation space and a releasing position where the primary conductor ends move transversely into a releasing position allowing the primary conductor ends to join into their contacts in the modules.

A circuit breaker design allows for the circuit breaker to have an overall width (i.e., measured along the circuit breaker's exposed outwardly-facing surface of its housing) that is narrower than achievable with known typical configurations, while at the same time still providing robust arc interruption capabilities. This is achieved in large part by providing a specific orientation of a moveable contact arm assembly and/or by providing a specific configuration of a current path within the housing.

A control system is designed to control an interrupter. The interrupter is started by a startup current to interrupt a main electric circuit. The startup current flows through an auxiliary electric circuit and has a current valve equal to or greater than a predetermined value. The control system includes a driving unit and a driven unit. The driving unit includes an intermediate electrical path to be connected to the main electric circuit. The driven unit is to be connected to the auxiliary electric circuit. When an abnormal current having a current value equal to or greater than a prescribed value flows through the intermediate electrical path, the driving unit uses, as a drive source for driving the driven unit, the abnormal current flowing through the intermediate electrical path. The driven unit supplies the auxiliary electric circuit with the startup current by being driven by the driving unit.

The present invention is directed to electrical wiring device that includes: a housing including a cover and a back body, the housing further including a plurality of line terminals and a plurality of feed-through load terminals, a plurality of receptacle load terminals substantially aligned with a plurality of receptacle openings; a fault protection circuit disposed inside the housing, having sensing components mounted to one side of a first PCB, the fault protection circuit being configured to provide a fault detection signal in response to detecting at least one type of predetermined fault condition; a circuit interrupter disposed inside the housing, the circuit interrupter being configured to couple the plurality respective terminals in response to a reset stimulus being applied to a reset button, the circuit interrupter being configured to decouple the respective plurality of terminals in a second state when the latching element and a reset pin are decoupled in response to the fault detection signal; and an indication circuit having an indicator to alert the user of device status.

An interrupter system includes a first coil and an interrupter electrically connected to the first coil. The interrupter includes: a first terminal; a second terminal electrically connected to the first terminal; a third terminal electrically separated from the first terminal and the second terminal; a heat generating element electrically connected to the third terminal; and an explosive configured to be ignited by the heat generating element to produce a gas for interrupting an electrical connection between the first terminal and the second terminal. The first coil is electrically connected to the heat generating element via the third terminal. Moreover, the first coil is configured to, when an abnormal current flows between the first terminal and the second terminal, generate an electric power for igniting the explosive from the abnormal current.

A miniature circuit breaker with quick current breaking capability which includes a miniature circuit breaker body, a current transformer CT1, a zero-sequence current transformer CT2 and a smart controller module. The miniature circuit breaker body is internally provided with a main arc extinguishing chamber, a fixed contact, a movable contact, a tripping mechanism, and a magnetic tripping push rod. The tripping mechanism includes a lock catch, a movable contact rocker arm, a jump pin, a connecting rod, and a tension spring. A rotated-hinge repulsive force structure is applied between the fixed contact and the movable contact. The tripping mechanism is further provided with a torsional spring to press the movable contact close to the fixed contact. A shunt tripping device controlling the miniature circuit breaker switch to be turned off is arranged in the smart controller module.

The present invention is directed to electrical wiring device that includes: a housing assembly including a cover assembly and a back body member, the cover assembly including a front cover having a plurality of receptacle openings, the housing assembly further including a plurality of line terminals and a plurality of feed-through load terminals, a plurality of receptacle load terminals substantially aligned with the plurality of receptacle openings; a separator portion disposed between the back body member and the cover assembly, the separator portion including a reset pin aperture accessible via a first major surface facing the front cover and a reset pin guide portion disposed on an opposite second major surface facing the back body member both being configured to accommodate a reset pin; and a latch block assembly including a central latch block portion configured to accommodate the reset pin and a latching element, the central latch block portion including an open side configured to accommodate the reset pin guide portion, the reset pin being substantially prevented by the reset pin guide portion from exiting the central latch block portion via the open side.

A multi-pole circuit breaker such as a residential electronic circuit breaker is provided. It includes a means to prevent a breaker mechanism from latching, i.e., a breaker armature from latching with a cradle if certain criterion is met. In particular, the multi-pole circuit breaker comprises a breaker mechanism including a breaker armature, a cradle and an armature latch bar to prevent the breaker armature from latching with the cradle. The armature latch bar includes a recessed feature that interfaces with the breaker armature, an armature latching surface that needs to be removed before the breaker mechanism can be latched and an armature latching lever that prevents a rotation of the breaker armature.