219 results about "Arc-fault circuit interrupter" patented technology

Resettable circuit interrupting devices, such as GFCI devices that include a reset lockout mechanism, are provided. The reset lockout comprises a member coupled to swing from a pivot which moves with a reset button to permit the resetting of electrical connections between input and output conductors if the circuit interrupting mechanism used to break the connection is non-operational or if an open condition exists.

In order to determine whether arcing is present in an electrical circuit, a sensor signal corresponding to current in said electrical circuit is processed. The sensor signal is filtered to determine the presence of noise in a predetermined frequency range and produce a corresponding filtered signal. The corresponding filtered signal is compared to a reference threshold voltage to generate an output signal potentially indicative of arcing. A selection is made of one from a plurality of available threshold voltages as the reference threshold voltage for use in the comparing operation. The detection operation supports either or both branch feeder arc fault detection and / or series arc fault detection.

This invention discloses a ground fault circuit interrupter capable of detecting its end of life, and is characterized by: a pair of flexible metal sheets connected to the power output end are added on the circuit board of the interrupter, and there is a pair of moving contacts on the metal sheets; there are two pairs of fixed contacts on the power output conductors; the two pairs of fixed contacts on the power output conductors respectively correspond to the moving contacts on the power input metal sheets and the moving contacts on flexible metal sheets, thus forming two groups and four pairs of switches. There is also a tripping apparatus on the circuit board, which can release / trip the interrupter, thus cutting off the power output of the interrupter. An end of life detection circuit has also been added to the circuit board. After the interrupter is energized, various components in the interrupter are automatically detected. If it is found that the interrupter has come to the end of its life, the reset button will be prevented from resetting, so that neither the load end of the interrupter nor the power output holes on the surface of the interrupter have any power output. This invention has powerful applications, with sound safety precautions, thus effectively ensuring the personal safety of the user as well as the safety of the appliances.

An arc fault circuit interrupter includes separable contacts electrically connected between line and load terminals, and a current sensor adapted to sense current flowing between the terminals and through the contacts. An arc fault detection circuit is adapted to collect a plurality of samples of the sensed current for a line cycle, determine a first slope of the sensed current at about a zero crossing of a line voltage, determine a magnitude of one of the samples at about the zero crossing, determine a second slope of the sensed current at another one of the samples having about the magnitude, with the first slope being opposite in polarity with respect to the second slope. The arc fault detection circuit calculates a difference between the slopes, and generates a trip signal as a function of the difference. An operating mechanism is adapted to open the contacts responsive to the trip signal.

Disclosed is an end-of-life status alarm indication circuit and method for indicating the failure of the primary contacts of a ground fault circuit interruption (GFCI) device to open when a ground fault circuit is detected by the GFCI device. The GFCI device will protect against the situation where the primary contacts of a GFCI device become welded together and will not open when a ground fault circuit is detected by the device. The alarm indication may be either an audible or visual indication.

A direct current arc fault circuit interrupter includes separable contacts and a trip circuit to trip open the contacts. The trip circuit includes a number of alternating current sensors structured to sense a current flowing through the separable contacts, a number of filter circuits cooperating with the AC current sensors to output a number of AC signals, a number of peak detectors cooperating with the filter circuits to output a number of peak current signals, and a processor cooperating with at least the peak detectors. The processor inputs the number of peak current signals as a plurality of peak current signals or inputs the number of peak current signals and determines the plurality of peak current signals. The processor also determines if the peak current signals exceed corresponding predetermined thresholds for a predetermined time, and responsively causes the contacts to trip open.

A circuit interrupter includes band pass filters cooperating with a current sensor to output bands having different, non-overlapping ranges of frequencies, peak detectors cooperating with the filters to detect corresponding peak current values, envelope detectors cooperating with the filters to detect corresponding occurrences from the bands being within corresponding predetermined magnitude ranges, a counter counting the occurrences, and a processor providing and disabling series arc detection when sensed current is greater than a first predetermined value. The processor determines tallies responsive to peak current values exceeding corresponding thresholds, determines series arcing from sensed current being less than the first predetermined value for a predetermined time, the tally for a current half-cycle being nonzero, and a count for the current half-cycle being different than the count for an immediately previous half-cycle of like polarity by at least a second predetermined value. A series chaos accumulator is increased responsive to series arcing.