Abstract: Various embodiments of the present invention are directed to a first trip unit that is configured to be coupled to a power distribution system arranged in a Zone Selective Interlocking (ZSI) arrangement. The first trip unit includes an Input/Output circuit including a ZSI input terminal and a ZSI output terminal, a heartbeat signaling module configured to transmit a second signal to a second trip unit in a lower-level zone than the first trip unit, responsive to the normal condition, a first monitoring module configured to monitor a first signal received by the first trip from a third trip unit in a higher-level zone, responsive to the normal condition, and a second monitoring module configured to detect the fault condition. Related systems, devices, and methods are also described.

Abstract: A method involves a circuit interrupter installation having a circuit interrupter with a plurality of poles and an ETU electrically connected with a neutral current sensor situated in proximity to a neutral conductor. The method includes determining that a plurality of fundamental frequency phase current vectors, when summed, are substantially equal to a fundamental frequency neutral current vector, and/or that a plurality of triplen odd-numbered harmonic phase current vectors, when summed, are substantially equal to a triplen odd-numbered harmonic neutral current vector. Responsive to the determining, the method includes outputting a notification which represents a possibility that a neutral current detection apparatus is mis-wired, and/or employing with the ETU a reverse vector that is an opposite of the fundamental frequency neutral current vector in the ongoing monitoring for an event that would trigger the movement of the circuit interrupter from the ON condition to the OFF or TRIPPED condition.

Abstract: Various embodiments of the present invention are directed to a first trip unit that is configured to be coupled to a power distribution system arranged in a Zone Selective Interlocking (ZSI) arrangement. The first trip unit includes an Input/Output circuit including a ZSI input terminal and a ZSI output terminal, a heartbeat signaling module configured to transmit a second signal to a second trip unit in a lower-level zone than the first trip unit, responsive to the normal condition, a first monitoring module configured to monitor a first signal received by the first trip from a third trip unit in a higher-level zone, responsive to the normal condition, and a second monitoring module configured to detect the fault condition. Related systems, devices, and methods are also described.

Abstract: A method involves a circuit interrupter installation having a circuit interrupter with a plurality of poles and an ETU electrically connected with a neutral current sensor situated in proximity to a neutral conductor. The method includes determining that a plurality of fundamental frequency phase current vectors, when summed, are substantially equal to a fundamental frequency neutral current vector, and/or that a plurality of triplen odd-numbered harmonic phase current vectors, when summed, are substantially equal to a triplen odd-numbered harmonic neutral current vector. Responsive to the determining, the method includes outputting a notification which represents a possibility that a neutral current detection apparatus is mis-wired, and/or employing with the ETU a reverse vector that is an opposite of the fundamental frequency neutral current vector in the ongoing monitoring for an event that would trigger the movement of the circuit interrupter from the ON condition to the OFF or TRIPPED condition.

Abstract: A frame module for a circuit breaker includes a first interface structured to connect to a trip unit, a second interface structured to connect to a frame, and a current rating storage unit structured to store a current rating associated with the frame and to provide the stored current rating to the trip unit when the trip unit is connected to the first interface.

Abstract: A circuit breaker includes a set of separable contacts moveable between a closed position and an open position, an operating mechanism configured to open the set of contacts, a conductor coupled to the set of contacts, a current transformer coupled to the conductor, and a trip circuit coupled to the operating mechanism and to the current transformer and configured to cause the operating mechanism to open the set of contacts when a current through the conductor exceeds a current threshold that is greater than a saturation threshold of the current transformer. The trip circuit is further configured to vary the current threshold during an interval following a closure of the set of the contacts and to provide a fixed current threshold thereafter.

Abstract: A frame module for a circuit breaker includes a first interface structured to connect to a trip unit, a second interface structured to connect to a frame, and a current rating storage unit structured to store a current rating associated with the frame and to provide the stored current rating to the trip unit when the trip unit is connected to the first interface.

Abstract: Molded case circuit breakers (MCCBs) have an MCCB body with at least one switch printed circuit board (PCB) holding between 1-4 recessed switches. The switch PCB has a bottom primary surface and an opposing top primary surface and a cover residing over the switch PCB and attached to the MCCB case body so that an outer end portion of the 1-4 switches held by the switch PCB extends through the cover.

Abstract: The disclosed concept relates to electrical switching apparatus, such as, but not limited to, molded case circuit breakers, and more particularly, to a connector assembly for mechanically and electrically connecting the accessory components housed within the electrical switching apparatus to equipment located outside of the electrical switching apparatus.

Abstract: A circuit breaker includes a set of separable contacts moveable between a closed position and an open position, an operating mechanism configured to open the set of contacts, a conductor coupled to the set of contacts, a current transformer coupled to the conductor, and a trip circuit coupled to the operating mechanism and to the current transformer and configured to cause the operating mechanism to open the set of contacts when a current through the conductor exceeds a current threshold that is greater than a saturation threshold of the current transformer. The trip circuit is further configured to vary the current threshold during an interval following a closure of the set of the contacts and to provide a fixed current threshold thereafter.

Abstract: An electrical switching apparatus includes a transductor circuit that senses a direct current between at least one input terminal and at least one output terminal and outputs an alternating current proportional to the direct current between the input terminal and the output terminal. The electrical switching apparatus also includes an alternating current electronic trip circuit configured to control pairs of separable contacts to separate based on the alternating current output from the transductor circuit.

Abstract: Molded case circuit breakers (MCCBs) have an MCCB body with at least one switch printed circuit board (PCB) holding between 1-4 recessed switches. The switch PCB has a bottom primary surface and an opposing top primary surface and a cover residing over the switch PCB and attached to the MCCB case body so that an outer end portion of the 1-4 switches held by the switch PCB extends through the cover.

Abstract: The disclosed concept relates to electrical switching apparatus, such as, but not limited to, molded case circuit breakers, and more particularly, to a connector assembly for mechanically and electrically connecting the accessory components housed within the electrical switching apparatus to equipment located outside of the electrical switching apparatus.

Abstract: An electrical switching apparatus includes a transductor circuit that senses a direct current between at least one input terminal and at least one output terminal and outputs an alternating current proportional to the direct current between the input terminal and the output terminal. The electrical switching apparatus also includes an alternating current electronic trip circuit configured to control pairs of separable contacts to separate based on the alternating current output from the transductor circuit.

Abstract: A metering apparatus is connectable to the terminals of a circuit breaker and includes a detection apparatus that is configured to detect a status of the breaker and one or more operational parameters of the breaker. The metering apparatus may further include a communication apparatus that is configured to communicate the status of the breaker and/or one or more operational parameters of the breaker to another device. The metering apparatus may additionally include a power input that is independent of the breaker. Alternatively or additionally, the metering apparatus can be configured to communicate with the other device via any of a variety of established protocols, with the metering apparatus being capable of retrofitting to change the communications protocol by which it communicates with the other device.

Abstract: Provided herein is a circuit breaker trip unit with a displaying device. The displaying device has a first displaying region, a second displaying region and optionally a third displaying region. The first displaying region is adapted to show one or more icons alone or together with text arranged in horizontal lines; the second displaying region is adapted to show text arranged in horizontal lines or graphics; the third displaying region is adapted to show text arranged in a horizontal line.

Abstract: A metering apparatus is connectable to the terminals of a circuit breaker and includes a detection apparatus that is configured to detect a status of the breaker and one or more operational parameters of the breaker. The metering apparatus may further include a communication apparatus that is configured to communicate the status of the breaker and/or one or more operational parameters of the breaker to another device. The metering apparatus may additionally include a power input that is independent of the breaker. Alternatively or additionally, the metering apparatus can be configured to communicate with the other device via any of a variety of established protocols, with the metering apparatus being capable of retrofitting to change the communications protocol by which it communicates with the other device.

Abstract: A circuit breaker includes a set of main separable contacts, an operating mechanism for operating the main separable contacts, a set of secondary separable contacts in series with the main separable contacts, and a solenoid mechanism for operating the secondary separable contacts. A first auxiliary switch is responsive to the operating mechanism, and a second auxiliary switch, electrically connected to the first auxiliary switch, is responsive to the solenoid mechanism. An input terminal for a control voltage is electrically connected to the first and second auxiliary switches. A first diode is electrically connected with a forward polarity between the first auxiliary switch and an output terminal. A second diode is electrically connected with a reverse polarity between the second auxiliary switch and the output terminal.