A terminal shield for a circuit breaker, formed of an electrically insulating material, protects an operator from inadvertently touching the load terminal that would otherwise be exposed on the bottom side of the circuit breaker: In accordance with an example embodiment of the invention, the terminal shield is integrated with a toroidally shaped current transformer sensor, to enable measuring the current in a load wire that has been inserted through an aperture in the terminal shield. Preferably there is an access hole in the front portion of the terminal shield, which allows the operator to insert a tool through the front face of the circuit breaker, to tighten the load terminal onto the load wire. The terminal shield with the integrated current transformer sensor enables standardization of load current sensing capability for circuit breakers and further enables ease of installation without clutter in the confined regions of the load center.

A fusible switch disconnect device includes a housing adapted to receive at least one fuse therein, and a switchable contact for connecting the fuse to circuitry. A tripping mechanism and control circuitry are provided to move the switchable contact to an open position in response to a predetermined electrical condition.

In one embodiment, there is a fault interrupter device comprising at least one sensor comprising at least one first transformer having at least one outer region forming an outer periphery and at least one inner hollow region. There is also at least one second transformer that is disposed in the inner hollow region of the at least one first transformer. The transformers can be substantially circular in configuration, and more particularly, ring shaped. In another embodiment there is a rotatable latch which is used to selectively connect and disconnect a set of separable contacts to selectively disconnect power from the line side to the load side. The rotatable latch is in one embodiment coupled to a reset button. In at least one embodiment there is a slider which is configured to selectively prevent the manual tripping of the device.

There is provided a neutral pole transformer module for a circuit breaker capable of minimizing an influence of external noise, detecting a neutral pole current at low manufacturing cost, and detecting a neutral pole current without modifying a configuration of an existing overcurrent relay or without installing an additional component in the existing overcurrent relay. The neutral pole transformer module for a circuit breaker comprises a ZCT configured to allow a transmission line of a neutral pole detection current output from the current transformer to pass therethrough and to provide a secondary output current signal obtained by reducing the neutral pole detection current in a predetermined ratio; a printed circuit board configured to convert the secondary output current signal into a voltage signal, and to differentiate the converted voltage signal and output the same; and an enclosure formed of an electrical insulator and enclosing the ZCT and the PCB.

A current transformer according to the present invention may comprise a magnetic core, a secondary coil, and a magnetic flux compensation member. A main circuit of an air circuit breaker penetrates the magnetic core. In addition, the secondary coil is arranged to be adjacent to the magnetic core, and a secondary current is induced through a current flowing in the main circuit. In addition, the secondary coil supplies the induced secondary current to a relay. The magnetic flux compensation member may be coupled to the magnetic core so as to correct magnetic flux of the secondary coil.

The present disclosure provides a high voltage and high current switch with zero-phase waiting and a control method. The switch includes two or more switching units connected in series, each of the switch unit modules includes a main switch circuit, an auxiliary switch circuit, a voltage-equalizing power supply circuit unit, a switch control and communication circuit unit, and a current transformer; and the auxiliary switch circuit and the voltage-equalizing power supply circuit unit are connected in parallel between two ends of the main switch circuit, and the current transformer is connected to the main switch circuit; an output of the current transformer is connected to the voltage-equalizing power supply circuit unit which supplies power to the switch control and communication circuit unit, and the switch control and communication circuit unit is configured to control the closing and opening of a main relay and an auxiliary relay.

A communications and processing module is provided. The communications and processing module is electrically coupleable to a circuit breaker to provide the circuit breaker with additional capabilities. The communications and processing module includes a housing, at least one electrical contact positioned in the housing, an output lug positioned in the housing, wherein an electrical path is defined between the at least one electrical contact and the output lug, at least one sensor positioned in the housing and operable to sense at least one operating condition of the circuit breaker, and at least one communications interface positioned in the housing and communicatively coupled to the at least one sensor, the communications interface operable to receive data from the at least one sensor that is indicative of the at least one sensed operating condition to facilitate exporting the received data to a remote computing device.

A module for detecting an electrical fault includes a housing; a first conductor and a second conductor; a first measurement toroid, positioned around the first conductor and around the second conductor, for measuring a differential current flowing between the first and second conductors; a second measurement toroid, positioned around the first conductor, for detecting an electric arc signal flowing through this conductor; a relay; an electronic processing circuit configured to switch the relay according to the current measured by the measurement toroids. The measurement toroids are aligned with one another and the first toroid takes the shape of an elongated tube and allows the differential protection to operate with its own current.

A fusible switch disconnect device includes a housing adapted to receive at least one fuse therein, and a switchable contact for connecting the fuse to circuitry. A current detecting element, a tripping mechanism, and control circuitry are provided to move the switchable contact to an open position in response to predetermined electrical current conditions in the device.

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.