An arc detection apparatus is provided. The arc detection apparatus detects an arc using an electrical energy, eliminates the possibility of a false arc detection caused by noise due to a power environment, increases accuracy of arc detection, and prevents fires that may occur in a home or an industrial site due to an arc occurrence.

In one example, a ground fault circuit interrupter is provided. It may include a current imbalance detection circuit configured to provide a leakage signal and a main processing circuit including a processor. The leakage signal may correspond to a current imbalance between a supply path and a return path. The processor may be configured to receive the leakage signal, analyze a time pattern of the leakage signal, determine whether a ground fault exists based on analysis of the time pattern, and generate a first trigger signal if the ground fault is determined to exist. The ground fault circuit interrupter may further include a back-EMF detection circuit configured to provide a back-EMF detection signal. Methods for detecting and responding to a ground fault are also provided.

In one example, a ground fault circuit interrupter is provided. It may include a current imbalance detection circuit configured to provide a leakage signal and a main processing circuit including a processor. The leakage signal may correspond to a current imbalance between a supply path and a return path. The processor may be configured to receive the leakage signal, analyze a time pattern of the leakage signal, determine whether a ground fault exists based on analysis of the time pattern, and generate a first trigger signal if the ground fault is determined to exist. The ground fault circuit interrupter may further include a back-EMF detection circuit configured to provide a back-EMF detection signal. Methods for detecting and responding to a ground fault are also provided.

In one example, a ground fault circuit interrupter is provided. It may include a current imbalance detection circuit configured to provide a leakage signal and a main processing circuit including a processor. The leakage signal may correspond to a current imbalance between a supply path and a return path. The processor may be configured to receive the leakage signal, analyze a time pattern of the leakage signal, determine whether a ground fault exists based on analysis of the time pattern, and generate a first trigger signal if the ground fault is determined to exist. The ground fault circuit interrupter may further include a back-EMF detection circuit configured to provide a back-EMF detection signal. Methods for detecting and responding to a ground fault are also provided.

In one example, a ground fault circuit interrupter is provided. It may include a current imbalance detection circuit configured to provide a leakage signal and a main processing circuit including a processor. The leakage signal may correspond to a current imbalance between a supply path and a return path. The processor may be configured to receive the leakage signal, analyze a time pattern of the leakage signal, determine whether a ground fault exists based on analysis of the time pattern, and generate a first trigger signal if the ground fault is determined to exist. The ground fault circuit interrupter may further include a back-EMF detection circuit configured to provide a back-EMF detection signal. Methods for detecting and responding to a ground fault are also provided.

In a DC feed system configured by a plurality of DC electrical circuits being combined, when an arc fault occurs, it is difficult to identify a DC electrical circuit in which an arc has occurred. For this reason, a DC electrical circuit protection apparatus includes: a plurality of DC electrical circuits, each of which has a current sensor provided in at least one of a positive or a negative electrical path and has arc noise absorbing mechanism on the upstream side of the current sensor; and an arc detection device which compares respective arc noise signal strengths of the DC electrical circuits from current signals detected by the current sensors of the DC electrical circuits, and based on the signal strengths, identifies a circuit in which an arc has occurred, wherein a DC electrical circuit in which an arc has occurred is identified.

A fault interrupt module includes a detector circuit, a counter circuit, and a switch circuit. The detector circuit is configured to detect faults as a difference in current between an input power line and a neutral line. The counter circuit configured to increment a fault count each time a fault is detected by the detector circuit, and the switch circuit is configured to terminate power to a load upon the fault count reaching a threshold count within a threshold time period.

A fault type determination method and device of a terminal unit for automation used in a power distribution network are disclosed. The method includes: for each line of incoming lines and outgoing lines of a distribution device, recording the number of faults occurring on the line; after a fault occurs, determining, according to the current and/or voltage on each line, whether automated reclosing is executed, and recording the number of executed automated reclosings; in a fault type determination period, for each line, if the number of faults occurring on the line is greater than the maximum number of automated reclosings allowed by the transformer substation side, or the fault is a repeat fault, then identifying the fault on the line as a permanent fault.

A fault type determination method and device of a terminal unit for automation used in a power distribution network are disclosed. The method includes: for each line of incoming lines and outgoing lines of a distribution device, recording the number of faults occurring on the line; after a fault occurs, determining, according to the current and/or voltage on each line, whether automated reclosing is executed, and recording the number of executed automated reclosings; in a fault type determination period, for each line, if the number of faults occurring on the line is greater than the maximum number of automated reclosings allowed by the transformer substation side, or the fault is a repeat fault, then identifying the fault on the line as a permanent fault.

A circuit interrupter including a line conductor, a neutral conductor, separable contacts structured to open to interrupt current flowing through the line and neutral conductors, a circuit interrupter circuit structured to detect a fault based on current flowing through the line and neutral conductors and to output a trip signal in response to detecting the fault, a trip circuit structured to trip open the separable contacts in response to the trip signal, and an audible indicator circuit electrically connected between the line and neutral conductors and being structured to output an audible sound in response to the trip circuit tripping open the separable contacts.