Abstract: A photovoltaic (PV) system includes a string of at least one PV module, and an arc fault detector (AFD) electrically coupled to the string. The AFD is configured to detect a non-DC electrical current that occurs within the string, and cause electrical contacts within the PV system to open as a result of the detected non-DC electrical current. The system includes a capacitor electrically coupled to the string and to the AFD such that the non-DC electrical current passes through the AFD and the capacitor.

Abstract: A protection apparatus is for a direct current electrical generating apparatus. The protection apparatus includes a first terminal; a second terminal; a third terminal; a fourth terminal; at least one current sensor structured to sense current flowing between the first and second terminals or between the third and fourth terminals; a voltage sensor structured to sense a voltage between the first terminal and the third terminal; at least one switch structured to interrupt the current flowing between the first and second terminals or between the third and fourth terminals; and a processor cooperating with the at least one current sensor, the voltage sensor and the at least one switch, and being structured to provide feed forward fault protection for the direct current electrical generating apparatus.

Abstract: A power circuit configured to generate and distribute DC electrical power, the power circuit includes a photovoltaic (PV) system that includes an array of PV modules electrically coupled to a combiner box, and an inverter positioned to receive DC electrical power from the array of PV modules and output AC electrical power. The PV system also includes a signal generator coupled to a first portion of the PV system, and a signal detector coupled to a second portion of the PV system, the signal detector configured to detect secondary signals generated at a loose connection of an electrical joint in the PV system, wherein the secondary signals result from a signal generated by the signal generator.

Abstract: An acoustic sensor apparatus includes a housing, a fastener structured to fasten together the housing and an electrical power conductor, an acoustic sensor structured to detect acoustic noise from the electrical power conductor and output a signal, and a circuit structured to detect an electrical conductivity fault from the signal.

Abstract: A photovoltaic (PV) system includes a string of at least one PV module, and an arc fault detector (AFD) electrically coupled to the string. The AFD is configured to detect a non-DC electrical current that occurs within the string, and cause electrical contacts within the PV system to open as a result of the detected non-DC electrical current. The system includes a capacitor electrically coupled to the string and to the AFD such that the non-DC electrical current passes through the AFD and the capacitor.

Abstract: An acoustic sensor system is for an electrical distribution system having a number of phases. The acoustic sensor system comprises: a plurality of sets of acoustic sensors structured to detect an electrical conductivity fault of the electrical distribution system. Each of the plurality of sets includes a number of acoustic sensors. Each of the number of acoustic sensors is for a corresponding one of the number of phases of the electrical distribution system.

Abstract: 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.

Abstract: A system and method for measuring voltage of a medium to high voltage line conductor is disclosed. The system includes an electrical insulator having a surface and an edge, the surface having an opening therein to allow passage of a line conductor therethrough in a direction generally perpendicular to the surface. The system also includes first and second electrodes positioned about the opening on the surface of the electrical insulator and spaced apart from one another to provide a common capacitive divider signal indicative of a voltage potential of the line conductor.

Abstract: An acoustic sensor apparatus includes a housing, a fastener structured to fasten together the housing and an electrical power conductor, an acoustic sensor structured to detect acoustic noise from the electrical power conductor and output a signal, and a circuit structured to detect an electrical conductivity fault from the signal.

Abstract: An acoustic sensor apparatus includes a housing; a clamp structured to clamp together the housing and an electrical power conductor; an acoustic sensor structured to detect acoustic noise from the electrical power conductor and output a signal; and a circuit structured to detect an electrical conductivity fault from the signal.

Abstract: An acoustic sensor system is for an electrical distribution system having a number of phases. The acoustic sensor system comprises: a plurality of sets of acoustic sensors structured to detect an electrical conductivity fault of the electrical distribution system. Each of the plurality of sets includes a number of acoustic sensors. Each of the number of acoustic sensors is for a corresponding one of the number of phases of the electrical distribution system.

Abstract: A protection apparatus is for a direct current electrical generating apparatus. The protection apparatus includes a first terminal; a second terminal; a third terminal; a fourth terminal; at least one current sensor structured to sense current flowing between the first and second terminals or between the third and fourth terminals; a voltage sensor structured to sense a voltage between the first terminal and the third terminal; at least one switch structured to interrupt the current flowing between the first and second terminals or between the third and fourth terminals; and a processor cooperating with the at least one current sensor, the voltage sensor and the at least one switch, and being structured to provide feed forward fault protection for the direct current electrical generating apparatus.

Abstract: 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.

Abstract: A string includes direct current electrical generating modules electrically connected in series to form a first end and a remote second end. A power line is electrically connected to one DC EGM at the first end. A return line is electrically connected to another DC EGM at the remote second end. A first string protector is in the power line of the string, and a second SP is in the return line of the string at the remote second end. One of the first and second SPs includes a number of an over current protector, an arc fault protector, a reverse current protector and a ground fault protector. The other one of the first and second SPs includes a number of an over current protector, an arc fault protector, a reverse current protector, a ground fault protector, and a remotely controlled switch in series with the power or return lines.

Abstract: A system and method for measuring voltage of a medium to high voltage line conductor is disclosed. The system includes an electrical insulator having a surface and an edge, the surface having an opening therein to allow passage of a line conductor therethrough in a direction generally perpendicular to the surface. The system also includes first and second electrodes positioned about the opening on the surface of the electrical insulator and spaced apart from one another to provide a common capacitive divider signal indicative of a voltage potential of the line conductor.

Abstract: A battery disconnect includes a housing, battery and load terminals, separable contacts electrically connected between the battery and load terminals, an operating mechanism structured to open and close the contacts, and a manual operator cooperating with the operating mechanism to open and close the contacts. A current sensor is structured to sense current flowing between the battery and load terminals. A circuit cooperates with the current sensor and the operating mechanism to trip open the contacts responsive to arc fault, overload and short circuit conditions associated with the sensed current. The circuit includes a first input structured to receive a remote on/off signal and a second input structured to receive an inhibit signal. The circuit cooperates with the operating mechanism to open and close the contacts responsive to the on/off signal, and to inhibit detection of the arc fault, overload and short circuit conditions responsive to the inhibit signal.

Abstract: An apparatus for repeatably generating electrical arcs for testing an electrical switching device, such as an arc fault circuit interrupter, includes a stationary electrode and a movable electrode that is moved along a path of travel by an electromechanical device under the control of a controller that receives data from either a current measuring device or a voltage measuring device to detect the initiation of an arc. The movable electrode is caused to first make physical contact with the stationary electrode, and then is moved away from the stationary electrode until an arc is detected. Additionally, the movable electrode may be moved towards and away from the stationary electrode according to a test profile to control the magnitude of the randomness of the arc.

Abstract: A battery disconnect includes a housing, battery and load terminals, separable contacts electrically connected between the battery and load terminals, an operating mechanism structured to open and close the contacts, and a manual operator cooperating with the operating mechanism to open and close the contacts. A current sensor is structured to sense current flowing between the battery and load terminals. A circuit cooperates with the current sensor and the operating mechanism to trip open the contacts responsive to arc fault, overload and short circuit conditions associated with the sensed current. The circuit includes a first input structured to receive a remote on/off signal and a second input structured to receive an inhibit signal. The circuit cooperates with the operating mechanism to open and close the contacts responsive to the on/off signal, and to inhibit detection of the arc fault, overload and short circuit conditions responsive to the inhibit signal.

Abstract: An apparatus for repeatably generating electrical arcs for testing an electrical switching device, such as an arc fault circuit interrupter, includes a stationary electrode and a movable electrode that is moved along a path of travel by an electromechanical device under the control of a controller that receives data from either a current measuring device or a voltage measuring device to detect the initiation of an arc. The movable electrode is caused to first make physical contact with the stationary electrode, and then is moved away from the stationary electrode until an arc is detected. Additionally, the movable electrode may be moved towards and away from the stationary electrode according to a test profile to control the magnitude of the randomness of the arc.

Abstract: An arc fault detector analyzes patterns in a sequence of counts of interval to interval increases or decreases in integrated current for patterns characteristic of arc faults. In AC systems, the interval can be a full cycle or in an alternative embodiment, the changes in integrated current for positive and negative half cycles are separately determined and then interleaved before the change counts are calculated. The count sequence is reset when patterns characteristic of phenomena other than an arc fault are detected to avoid nuisance trips.