An arc fault detection system includes a high frequency detector module structured to detect first spectral content of power having a frequency in a first frequency range, a number of arc fault circuit interrupters each having separable contacts, a low frequency detector module structured to detect second spectral content of power having a frequency in a second frequency range, a control unit structured to control the separable contacts to trip open, and an arc fault detection unit structured to detect an arc fault based on the detected first and second spectral content of the power and to cause the control unit to control the separable contacts to trip open in response to detecting the arc fault. A communication bus provides communication between the high frequency detector and the arc fault circuit interrupters and the first frequency range includes frequencies that are higher than frequencies in the second frequency range.

A method involves a circuit interrupter installation having a circuit interrupter with a plurality of poles and an ETU electrically connected with a neutral current sensor situated in proximity to a neutral conductor. The method includes determining that a plurality of fundamental frequency phase current vectors, when summed, are substantially equal to a fundamental frequency neutral current vector, and/or that a plurality of triplen odd-numbered harmonic phase current vectors, when summed, are substantially equal to a triplen odd-numbered harmonic neutral current vector. Responsive to the determining, the method includes outputting a notification which represents a possibility that a neutral current detection apparatus is mis-wired, and/or employing with the ETU a reverse vector that is an opposite of the fundamental frequency neutral current vector in the ongoing monitoring for an event that would trigger the movement of the circuit interrupter from the ON condition to the OFF or TRIPPED condition.

A circuit interrupter including a first electrical conductor, a second electrical conductor, separable contacts, an operating mechanism configured to open and close said separable contacts, a trip circuit configured to trip open said separable contacts, a ground fault detection circuit configured to sense a difference between a current through the first electrical conductor and a current through the second electrical conductor and to output an output signal based on said sensed difference, a power supply, a confirmation circuit structured to input a confirmation signal to the power supply, and a processor configured to receive said direct current power and said output signal. The processor is configured to determine whether a characteristic of said confirmation signal is present in said output signal and to control the trip circuit based on said determination.

A lamp is provided. The lamp includes at least one light emitting diode (LED) and an electronic circuit configured to provide power to the at least one LED. The lamp includes at least one flat circuit board having mounted thereto the at least one LED and the electronic circuit. The at least one flat circuit board acts as a heatsink to dissipate heat from the at least one LED and acts as a plurality of circuit paths for the electronic circuit and the at least one LED.

A lamp is provided. The lamp includes at least one light emitting diode (LED) and an electronic circuit configured to provide power to the at least one LED. The lamp includes at least one flat circuit board having mounted thereto the at least one LED and the electronic circuit. The at least one flat circuit board acts as a heatsink to dissipate heat from the at least one LED and acts as a plurality of circuit paths for the electronic circuit and the at least one LED.

Distance protection of electric power delivery systems are disclosed herein where a fault within a zone of protection is detected using time-domain fault detection supervised by frequency-domain fault detection. The distance fault detection may be asserted when the real or imaginary parts of the time-domain operating and polarizing quantities are both positive or both negative and an angle between the frequency domain operating and polarizing quantities is within a predetermined range. Additional security may be provided using a level check, a sign consistency check, or a disturbance detector.

Distance protection of electric power delivery systems are disclosed herein where a fault within a zone of protection is detected using time-domain fault detection supervised by frequency-domain fault detection. The distance fault detection may be asserted when the real or imaginary parts of the time-domain operating and polarizing quantities are both positive or both negative and an angle between the frequency domain operating and polarizing quantities is within a predetermined range. Additional security may be provided using a level check, a sign consistency check, or a disturbance detector.

A device for detecting an arc fault in a polyphase electrical installation comprises: a high-frequency measuring system coupled to at least two electrical phase lines of the installation, said measuring system being configured to extract a first signal representative of high-frequency components of electrical currents flowing through said phase lines; a plurality of low-frequency measuring systems, each coupled to one electrical phase line of the installation, each being configured to acquire a second signal representative of the alternating line current flowing through the corresponding phase line; and a data-processing module programmed to detect an arc fault on the basis of the second signals and of the first signal.

A device for detecting an arc fault in a polyphase electrical installation comprises: a high-frequency measuring system coupled to at least two electrical phase lines of the installation, said measuring system being configured to extract a first signal representative of high-frequency components of electrical currents flowing through said phase lines; a plurality of low-frequency measuring systems, each coupled to one electrical phase line of the installation, each being configured to acquire a second signal representative of the alternating line current flowing through the corresponding phase line; and a data-processing module programmed to detect an arc fault on the basis of the second signals and of the first signal.

Techniques for determining whether a downed conductor is present in an electrical power distribution network that includes a neutral line and a plurality of energized conductors are disclosed. For example, a sampled neutral current signal is received, the sampled current signal including a plurality of values, each of the values representing an amplitude of current that flows in of the neutral conductor at a particular time; an unfiltered current signal is generated based on the sampled current signal; the sampled current signal is filtered to generate a filtered current signal; the unfiltered current signal and the filtered current signal are compared to generate an error signal; and the error signal is analyzed to determine whether at least one of the plurality of conductors is a downed conductor.