At least one example embodiment provides a low-voltage circuit breaker for interrupting a low-voltage circuit. The low-voltage circuit breaker includes at least one first current sensor configured to determine a magnitude of an electrical current of the low-voltage circuit, an interruption unit with contacts configured to interrupt the low-voltage circuit, an electronic trip unit connected to the first current sensor and the interruption unit and configured in such a way that an interruption of the low-voltage circuit is instigated upon current or/and current period limit values being exceeded, and a power supply unit configured to supply power to the electronic trip unit and to at least one additional component of the low-voltage circuit breaker, wherein a second current sensor is between the power supply unit and the at least one additional component, said second current sensor configured to determine the magnitude of the current of the additional component.

A circuit breaker is for interrupting an electric current circuit when current and/or current time period thresholds are exceeded. The circuit breaker includes at least one control unit, to which energy is supplied by an energy converter. A primary winding of the energy converter is formed by a conductor of the electric current circuit. The core of the energy conductor surrounding the electric current circuit conductor is used as the primary winding. A secondary winding surrounds a section of the core. The secondary winding additionally surrounds an inductor core, arranged relative to the core using an insulating spacer element. The secondary winding and the inductor core are at least party magnetically shielded from the primary winding by a shielding plate guided through the core.

An electric meter in a utility box is capable of detecting arcing conditions between meter blades and a meter socket in the utility box at a premises. The electric meter includes a current-transformer structure forming an enclosed space. An arc detection antenna can be placed in the enclosed space along with the current transformer. The current-transformer structure is placed on a baseplate of the electric meter near the blades connected to the meter socket. Leads of the arc detection antenna are electrically connected to an arc detection circuit configured to detect arcing conditions based on the signal received from the arc detection antenna. If it is determined that the arcing condition is present, the electric meter may be activated to interrupt the connection between the power source and the premises.

A leakage current protection device includes a shell and a core assembly disposed within the shell. The core assembly includes a control circuit board, a trip assembly disposed on the control circuit board, and an input end and an output end connected to the trip assembly. The trip assembly includes a first driving member movable linearly in a first direction and a second driving member pivotable around a pivotal support axis, where the first and second driving members are mechanically engaged with each other and move together with each other. The second driving member has two driving points configured to move in a second direction as the second driving member pivots, the second direction being non-parallel to the first direction. Movements of the two driving points of the second driving member in the second direction are operable to electrically connect or disconnect the input and output ends.

A set of electrical protection devices with two levels that are connected in series, the first level including a circuit breaker that is referred to as the first or upstream circuit breaker and the second level including one or more circuit breakers referred to as second or downstream circuit breakers, which are connected in parallel with respect to one another.

The trip for the upstream circuit breaker, instead of including what are referred to as instantaneous protection means, includes, firstly, a first trip chain making it possible to adjust the long-delay trip curve for inverse time and the short-delay trip curve with a no-trip time and, secondly, a second trip chain including an optical sensor that is capable of discerning light between 300 and 450 nm by eliminating visible and infrared light so as to eliminate the light that is characteristic of gas jets emitted by the one or more circuit breakers referred to as downstream circuit breakers during a switching operation, and means for simultaneously measuring the current level and the maximum threshold of light emitted at the busbars, this second trip chain being capable of causing the upstream circuit breaker to trip when the current exceeds a predetermined value and the light emitted exceeds a predetermined threshold for emitted light.

A system and method are provided to detect a fault on a circuit. A current sensor is provided for sensing current on at least one line conductor and/or a neutral conductor on a circuit, and a switch is operated between at least first and second positions to selectively control a signal pathway on the at least one line conductor or the neutral conductor in relations to the sensor. The sensor performs a first current measurement corresponding to current across one conductor from the at least one line conductor and the neutral conductor in the first position, and a second current measurement corresponding to a current balance or imbalance between the conductors in the second position. The current sensor outputs the first current measurement for detecting an arc fault in the first position, or the second current measurement for detecting a ground fault in the second position.

In a circuit breaker arrangement, this disclosure describes a method and circuit design enables a current transformer to be used to detect ground faults in circuit breakers (such as a main-tie-main circuit breakers) that have been designed to receive signals from Rogowski coils.

A switching device includes: an electronic trip unit; an actuator; a switching mechanism connected via the actuator to the electronic trip unit; a stationary contact; a mobile contact, which is coupled to the switching mechanism; and an alarm module. The alarm module includes: a first, a second, and a third connector; a first relay having a first contact which is connected to the first connector and having a second contact which is connected to the second connector; a second relay with a first contact which is connected to the third connector; and a control unit which is coupled on an output side to a control side of the first relay and to a control side of the second relay, and on the input side to the electronic trip unit.

The present invention relates to a trip device for a molded case circuit breaker and, more specifically, to an electronic trip device for a molded case circuit breaker. The electronic trip device for a molded case circuit breaker, according to one embodiment of the present invention, comprises: a trip part case having a plurality of phases; a trip part terminal provided at the rear surface part of the trip part case and provided for each phase; and a voltage sensing conductor coupled between the rear surface part and the trip part terminal and provided for each phase, wherein the voltage sensing conductor provided for each phase is formed to have the same shape and the same size.

This monitoring unit (1) for monitoring an electrical circuit breaker (D) includes: a central body including: an interconnection device (120) capable of receiving primary voltages (V1) from the circuit breaker, and comprising an electrical power circuit (1220) for converting the primary voltages to secondary voltages (V2); a control device (110), for measuring the secondary voltages (V2) delivered by the power circuit (1220), a removable electrical power supply module (20), comprising a power converter (203), configured to transform the collected primary voltages (V1) into an additional secondary voltage (V2) and to supply electrical power to a shared electrical power supply bus (1102) of the control device (110).