Abstract:
An electronic trip unit which includes a processing unit and a comparator circuit. The processing unit receives an input voltage, and a reset signal to reset the electronic trip unit, and generates a trip signal when sensed current of the electronic trip unit exceeds a predetermined threshold. The comparator circuit includes a first comparator which receives the trip signal from the processing unit and compares the trip signal with a predetermined reference voltage determined based on the reset signal, and a second comparator which compares a voltage generated by a power supply with the predetermined reference voltage. The comparator circuit determines whether the trip signal is for a valid trip event based comparison results of the first comparator and the second comparator.
Abstract:
An electronic trip unit which includes a processing unit and a comparator circuit. The processing unit receives an input voltage, and a reset signal to reset the electronic trip unit, and generates a trip signal when sensed current of the electronic trip unit exceeds a predetermined threshold. The comparator circuit includes a first comparator which receives the trip signal from the processing unit and compares the trip signal with a predetermined reference voltage determined based on the reset signal, and a second comparator which compares a voltage generated by a power supply with the predetermined reference voltage. The comparator circuit determines whether the trip signal is for a valid trip event based comparison results of the first comparator and the second comparator.
Abstract:
A restored metallic extrusion processing element comprises a tubular metal core around which is consolidated a powdered metal extrusion component that includes metallurgically bonded interior shell and exterior working portions. The interior shell portion covers the core and is characterized by a first multiple-crystalline microstructure, and the exterior working portion is characterized by a second multiple crystalline microstructure of densified powdered metal particles. The exterior working portion has an outside surface including outer working surface features that extend along the length of the extrusion processing element. A bond interface of metallurgical type defines a crystalline microstructure boundary between the first and second multiple-crystalline microstructures.
Abstract:
A system includes a sensor configured to provide a signal related to an operating condition of a component, a memory for storing values representative of the operating condition, and a processor coupled to the sensor and to the memory. The processor is programmed to calculate a first value of the operating condition during a first period of time based on the stored values, calculate a second value of the operating condition during a second period of time using the first value, and determine a status of the component using the second value.
Abstract:
A trip unit for a circuit breaker having at least one sensor for monitoring a current in a protected circuit and a tripping system is provided. The trip unit includes a first controller operably coupled to receive a current signal from the at least one sensor and electrically coupled to the tripping system. The first controller includes a first processor that transmits a first signal to the tripping system in response to a detection of a first undesired condition. A second controller is operably coupled to receive the current signal from the at least one sensor and is electrically coupled to the tripping system in parallel with the first controller. The second controller includes a second processor that detects the first condition and transmits a second signal to the tripping system after a predetermined first time period.
Abstract:
A diagnostic system and a diagnostic method for a thermistor amplifier circuit are provided. The system includes a transistor electrically coupled to a controllable variable resistor having a predetermined resistance. The transistor applies a test voltage signal to the circuit indicative of a first temperature value. An amplitude of the test voltage value is indicative of a simulated thermistor temperature value. The microprocessor determines a test temperature value based on the amplitude of an output voltage of the circuit. The microprocessor also determines an inaccuracy value based on the test temperature value and the simulated thermistor temperature value.
Abstract:
A restored metallic extrusion processing element comprises a tubular metal core around which is consolidated a powdered metal extrusion component that includes metallurgically bonded interior shell and exterior working portions. The interior shell portion covers the core and is characterized by a first multiple-crystalline microstructure, and the exterior working portion is characterized by a second multiple crystalline microstructure of densified powdered metal particles. The exterior working portion has an outside surface including outer working surface features that extend along the length of the extrusion processing element. A bond interface of metallurgical type defines a crystalline microstructure boundary between the first and second multiple-crystalline microstructures.
Abstract:
A circuit breaker apparatus is provided and includes a trip mechanism which is coupled to an electrical circuit and which is configured to interrupt an operation of the electrical circuit when the trip mechanism is actuated, an electronic trip unit in signal communication with and configured to actuate the trip mechanism when pre-selected conditions are satisfied, and a rating plug coupled to the electronic trip unit and configured to operate in a first mode in response to a receipt of a transmitted control signal at the rating plug, and to otherwise operate in a second mode, the first and second modes being respectively associated with first and second ones of the pre-selected conditions to be correspondingly transmitted to the electronic trip unit by which the electronic trip unit determines whether to actuate the trip mechanism.
Abstract:
A circuit breaker configured to be remotely operated is disclosed. The circuit breaker includes a set of main contacts configured to connect between an electrical source and an electrical load, an operating mechanism in operable communication to open and close the main contacts, and a remotely operable drive system configured to open and close the main contacts separate from actuation of the operating mechanism. The drive system includes a motor responsive to first and second control signals, a primary drive responsive to the motor, and an opening spring responsive to the primary drive, the main contacts being responsive to the opening spring. In response to the first control signal, the primary drive moves to charge the opening spring, and in response to the second control signal and the main contacts being closed, the primary drive moves to allow the opening spring to discharge thereby resulting in the main contacts opening independent of the motor.