摘要:
A testing device for detecting and locating an arcing fault in an electrical system includes a detector circuit for detecting one or more characteristics of the arcing fault proximate the arcing fault and outputting a responsive signal. An annunciator speaker or display annunciates the responsive signal when the detector circuit is proximate the arcing fault, in order to locate the arcing fault in the electrical system.
摘要:
A system includes a number of electrical switching apparatus having separable contacts, an operating mechanism structured to open and close the separable contacts, a trip mechanism cooperating with the operating mechanism to trip open the separable contacts, a test circuit structured to test the trip mechanism and determine a failure to protect condition thereof, and a communication circuit structured to communicate the failure to protect condition. The system also includes an electrical distribution panel having a housing housing the number of electrical switching apparatus, and a communication interface structured to receive the failure to protect condition from the communication circuit and annunciate the failure to protect condition.
摘要:
A system includes a number of electrical switching apparatus having separable contacts, an operating mechanism structured to open and close the separable contacts, a trip mechanism cooperating with the operating mechanism to trip open the separable contacts, a test circuit structured to test the trip mechanism and determine a failure to protect condition thereof, and a communication circuit structured to communicate the failure to protect condition. The system also includes an electrical distribution panel having a housing housing the number of electrical switching apparatus, and a communication interface structured to receive the failure to protect condition from the communication circuit and annunciate the failure to protect condition.
摘要:
A circuit breaker includes separable contacts, an operating mechanism structured to open and close the separable contacts, and a trip circuit including a trip coil and a fault detector. The fault detector energizes the trip coil to cause the operating mechanism to open the separable contacts. A test circuit is structured to test the trip coil and determine an open circuit condition thereof. An annunciation circuit is structured to annunciate the open circuit condition of the trip coil.
摘要:
A hybrid monolithic IC that is standardized for controlling various types of electrical equipment, such as circuit breakers, motor controllers and the like. The IC is a hybrid monolithic IC, fabricated in CMOS technology, The shortcomings of utilizing CMOS technology for linear or analog circuitry is overcome by the implementation of the IC to provide a monolithic IC that is relatively less expensive than using multiple ICs or a single IC fabricated from biCMOS technology.
摘要:
An arc fault circuit interrupter includes separable contacts, an operating mechanism, a current sensor sensing current flowing through the contacts and outputting a sensed current, and a processor determining and storing peak values of the sensed current for plural half-cycles. The processor provides arc fault detection, determines whether a first predetermined plurality of half-cycles occur in succession and correspond to non-unity power factor, and responsively inhibits the detection for a first predetermined time, and whether a second predetermined plurality of half-cycles occur in succession, each with smaller peak amplitude than that of an immediately preceding half-cycle of like or differing polarity, and responsively inhibits the detection for a second predetermined time. The processor determines that the detection is not inhibited for the first and second predetermined times, and responsively indicates that any of the half-cycles having a peak amplitude greater than a predetermined amount is a parallel arc.
摘要:
A miniature circuit breaker includes separable contacts, an operating mechanism structured to open and close the separable contacts, a microprocessor including a thermal overload predictive function, and a shunt wire in series with the separable contacts. The shunt wire is structured to measure current flowing through the separable contacts for the thermal overload predictive function and an arc fault protective function.
摘要:
A hybrid monolithic IC that is standardized for controlling various types of electrical equipment, such as circuit breakers, motor controllers and the like. The IC is a hybrid monolithic IC, fabricated in CMOS technology. The shortcomings of utilizing CMOS technology for linear or analog circuitry is overcome by the implementation of the IC to provide a hybrid monolithic IC that is relatively less expensive than using multiple IC's or a single IC fabricated from biCMOS technology. Also, by utilizing a single IC, such control and monitoring circuitry can be located in existing electrical equipment. The IC includes an on-board microprocessor, an A/D subsystem and various input/output devices which make it adaptable for use in various types of electrical equipment. In order to improve the resolution of the A/D subsystem, circuitry is provided, which includes current and voltage ranging amplifiers for ranging analog input voltage and current signals and compensating internal offsets, in such amplifiers, inherent in CMOS linear circuits which can affect the accuracy of the least significant bit.
摘要:
A monitor/analyzer for an ac electrical system can be programmed through a display on the front panel to respond to selected events by generating triggers signals when selected monitored electrical parameters including neutral current exceed programmed thresholds. The trigger signals initiate simultaneous waveform capture of multiple waveforms in the ac system. Multiple trigger signals result in sequential waveform capture so that if a plurality of triggers are programmed for the same event, extended waveform data is captured for the event. Alarm screens are generated in response to the events, as well as for hardware failure, an excessive neutral-to-ground voltage or reverse sequence.
摘要:
A power supply for converting a plurality of alternating current (AC) and direct current (DC) input line voltages to a DC output voltage includes a converter for converting the input voltages to an intermediate voltage at a first node; a switching regulator having a power voltage at a second node for providing a reference voltage therefrom, and for providing a switching signal at a third node from the reference voltage and a feedback voltage; a circuit for electrically interconnecting the first node to the second node whenever the intermediate voltage exceeds a predetermined voltage; a transformer including a primary winding electrically interconnected with the first node, and a secondary winding having a secondary voltage; a feedback circuit cooperating with the transformer for providing the feedback voltage therefrom; a switching circuit responsive to the switching signal at the third node for switching an electrical current from the first node through the primary winding; and a circuit electrically interconnected with the secondary winding for converting the secondary voltage to the output voltage.