Apparatus and method to detect a series arc fault of an electrical circuit

摘要

An apparatus is for a power circuit providing an alternating current to a load. The apparatus includes a high frequency current sensor structured to cooperate with the power circuit to provide a high frequency current signal. A voltage zero crossing detector is structured to cooperate with the power circuit to provide a voltage zero crossing signal. A high pass filter is structured to provide a filtered current signal from the high frequency current signal. A threshold comparator is structured to provide an output when the filtered current signal exceeds a predetermined value. A processor is structured to receive the voltage zero crossing signal and the output of the threshold comparator and output a trip signal in response to undesired series arcing by detecting an unsymmetrical high frequency signal for a predetermined number of cycles.