Arc fault detection system and method and circuit interrupter employing same

A DC arc fault detection module includes an LF current section, an LF voltage section, and an HF current section having a plurality of outputs, each output being associated with a respective one of a plurality of frequency sub-bands. The HF current section is structured to, for each of the frequency sub-bands, (i) detect a rise in energy of the frequency sub-band above a first predetermined threshold level for at least a certain amount of time and (ii) cause the associated output to indicate a rise in energy detection in response to detecting the rise in energy above the associated threshold level for at least the associated certain amount of time. The module includes a processing device structured to determine whether a DC arc fault has occurred based on the outputs from the LF and HF current and LF voltage sections.