Abstract: Systems and methods for sensing current utilize a coil-less sensor based circuit to detect current. The current sensing circuit includes a first conductive line segment that carries mains AC current, and a second conductive line segment conductively coupled in electrical parallel to the first line segment. The coil-less sensor is mounted between the two conductive line segments proximate to and generally opposite the second conductive line segment. Any suitable coil-less sensor may be used, including Hall effect sensors, tunneling magneto resistive (“TMR”) sensors, anisotropic magneto resistive (“AMR”) sensors, and other types of sensors that do not use coils to sense current. This arrangement results in two magnetic fields being induced that are additive at the coil-less sensor, which allows the sensor to produce a higher output voltage, thereby providing a more accurate current sensor.

Abstract: A state of a tripping solenoid in a circuit breaker is determined by a primary coil and a secondary coil wound around a hollow body of a solenoid. The secondary coil is positioned within magnetic coupling distance from the primary coil and is configured to produce a sensing voltage based on the primary coil voltage. A ferromagnetic plunger positioned in the hollow body, is configured to slide axially to a tripped position to trip the circuit breaker when a trip voltage is applied to the primary coil. A plunger position detecting circuit connected to the secondary coil, is configured to detect the position of the plunger in the hollow body of the solenoid based on the sensing voltage. A reduction or absence of the sensing voltage indicates a faulty or broken connection in the primary coil.

Abstract: A ground fault sensing circuit system includes a current transformer having a first winding and a second winding on opposite halves of the current transformer, outputting first and second signals, each winding coupled to a processor that determines information about respective currents in conductors monitored by the current transformer, based on a combination of the first and second signals. In another embodiment, the current transformer has a third winding wrapped continuously around both halves of the current transformer, overlapped with the first and second windings, the third winding outputting a third signal coupled to the processor, which determines information about respective currents in conductors monitored by the current transformer, based on a combination of the first, second, and third signals.

Abstract: A state of a tripping solenoid in a circuit breaker is determined by a primary coil and a secondary coil wound around a hollow body of a solenoid. The secondary coil is positioned within magnetic coupling distance from the primary coil and is configured to produce a sensing voltage based on the primary coil voltage. A ferromagnetic plunger positioned in the hollow body, is configured to slide axially to a tripped position to trip the circuit breaker when a trip voltage is applied to the primary coil. A plunger position detecting circuit connected to the secondary coil, is configured to detect the position of the plunger in the hollow body of the solenoid based on the sensing voltage. A reduction or absence of the sensing voltage indicates a faulty or broken connection in the primary coil.

Abstract: A ground fault sensing circuit system includes a current transformer having a first winding and a second winding on opposite halves of the current transformer, outputting first and second signals, each winding coupled to a processor that determines information about respective currents in conductors monitored by the current transformer, based on a combination of the first and second signals. In another embodiment, the current transformer has a third winding wrapped continuously around both halves of the current transformer, overlapped with the first and second windings, the third winding outputting a third signal coupled to the processor, which determines information about respective currents in conductors monitored by the current transformer, based on a combination of the first, second, and third signals.

Abstract: An energy monitoring system for retrofitting a miniature circuit breaker load center 100, comprises energy monitoring module 120, data bus 140, and main controller 110. The energy monitoring module attaches onto miniature circuit breaker 130, forming a combined shape that fits into a branch circuit space of the load center. An attachment connector 320 electrically and mechanically connects the energy monitoring module to load terminal 318 of the circuit breaker. An energy sensing circuit 314 in the energy monitoring module senses energy passing through the circuit breaker and transmits data signals over the data bus to the main controller. The main controller has a shape that fits into another branch circuit space of the load center. The main controller wirelessly transmits to a network, information based on the data signals received on the data bus. The main controller provides operating power via the data bus, to the energy monitoring module.

Abstract: A circuit breaker includes a trip mechanism having reduced trip movement and an integrated signal flag. The trip mechanism includes a spring-biased trip lever and a latching member for keeping the trip lever in an on or latched position. Upon occurrence of an abnormal current condition, the latching member is moved away from the trip lever to trip the trip mechanism. The latching member also has a catch mechanism designed to catch the trip lever after it is released, thereby halting further progress of both the trip lever and the latching member. As a result, less space is needed within the circuit breaker for trip movement compared to existing solutions. Moreover, the location of the catch mechanism on the latching member is selected such that the halting of the latching member places the integrated signal flag in an optimal viewing position within a viewing window.

Abstract: An overload relay is provided for electrical equipment, such as a motor. The overload relay includes a set of electrical contacts, a trip mechanism and a single-arm, a set of monolithic compliant mechanism actuators. The trip mechanism has a normal position and a tripped position. The normal position allows electrical connection between the electrical contacts, and the tripped position interrupts electrical connection between the electrical contacts in response to detection of a high current condition. The single-arm actuator is formed of an electrically conductive material, and includes a compliant hinge and a single bar connected to the hinge. The single bar is electrically coupled to the line contact or the load contact. Under the high current condition, one of first and second ends of the single bar deflects relative to the compliant hinge to cause the trip mechanism to move into the tripped position.

Abstract: An overload relay is provided for electrical equipment, such as a motor. The overload relay includes a set of electrical contacts, a trip mechanism and a single-arm, a set of monolithic compliant mechanism actuators. The trip mechanism has a normal position and a tripped position. The normal position allows electrical connection between the electrical contacts, and the tripped position interrupts electrical connection between the electrical contacts in response to detection of a high current condition. The single-arm actuator is formed of an electrically conductive material, and includes a compliant hinge and a single bar connected to the hinge. The single bar is electrically coupled to the line contact or the load contact. Under the high current condition, one of first and second ends of the single bar deflects relative to the compliant hinge to cause the trip mechanism to move into the tripped position.

Abstract: A circuit breaker includes a trip mechanism having reduced trip movement and an integrated signal flag. The trip mechanism includes a spring-biased trip lever and a latching member for keeping the trip lever in an on or latched position. Upon occurrence of an abnormal current condition, the latching member is moved away from the trip lever to trip the trip mechanism. The latching member also has a catch mechanism designed to catch the trip lever after it is released, thereby halting further progress of both the trip lever and the latching member. As a result, less space is needed within the circuit breaker for trip movement compared to existing solutions. Moreover, the location of the catch mechanism on the latching member is selected such that the halting of the latching member places the integrated signal flag in an optimal viewing position within a viewing window.

Abstract: A flexible thermal trip actuator unit for a circuit breaker is disclosed. The circuit breaker prevents electrical connection between a power line source in the event of an over current. The circuit breaker includes a line connector, a load connector and a trip mechanism. The trip mechanism has an on position allowing electrical connection between the line connector and the load connector, a tripped position interrupting electrical connection between the line connector and the load connector in response to detection of a high current condition, and an off position which is required before resetting the trip mechanism to the on position. The actuator unit has a cold bar coupled to the trip mechanism, a compliant hinge and a parallel hot bar electrically coupled to the load connector. The cold bar deforms from a high current to cause the trip mechanism to assume the tripped position.