Patent ID: 7925458

Claim:
A method in an arc fault detecting device capable of being electrically connected to an electrical wiring system between line side phase and neutral conductors and load side phase and neutral conductors, said method detecting the occurrence of arcing of a conductor by monitoring the current on an AC power line, said method comprising: detecting current in said conductor of the electrical wiring system and generating a signal representative of the detected current; generating at least one modified signal which represents the filtered or unfiltered current detected in the conductor; and receiving the at least one modified signal by a controller and performing the following by the controller: generating a SINE signal having half cycles and zero crossings from a raw input signal, or a signal from a finite impulse response (FIR) filter, or a signal from an infinite impulse response (IIR) filter; comparing the generated SINE signal with the at least one signals generated from the signal modifying means to generate a DELTA signal; analyzing the DELTA signal for at least one characteristic representative of the occurrence of an arc; and generating an output signal upon detection of the at least one characteristic representative of the occurrence of an arc, wherein the step of detecting current provides for the use of a current transformer, wherein the step of generating at least one modified signal provides a CURRENT signal representative of the current in the line, wherein the CURRENT signal is used by the controller to generate the SINE signal, and wherein the CURRENT signal is fed to a multipoint running finite impulse response filter to smooth the signal prior to being used to generate the SINE signal.