Electrical switching apparatus and method employing acoustic and current signals to distinguish between parallel and series arc faults

An electrical switching apparatus for detecting and distinguishing a fault of a power circuit, said electrical switching apparatus comprising:

• a first lug;
• a second acoustic lug structured to be electrically connected to said power circuit;
• a third acoustic lug structured to be electrically connected to said power circuit;
• separable contacts electrically connected in series between said first lug and said second acoustic lug;
• an operating mechanism structured to open and close said separable contacts;
• a first acoustic sensor coupled to said second acoustic lug, said first acoustic sensor being structured to sense a first acoustic signal from said second acoustic lug, said first acoustic signal being operatively associated with the fault of said power circuit;
• a second acoustic sensor coupled to said third acoustic lug, said second acoustic sensor being structured to sense a second acoustic signal from said third acoustic lug, said second acoustic signal being operatively associated with the fault of said power circuit;
• a third current sensor structured to sense a current flowing between said first lug and said second acoustic lug;
• and
• a circuit inputting said first and second sensed acoustic signals and said sensed current, said circuit structured to detect and distinguish a parallel arc fault or a series arc fault from said first and second sensed acoustic signals and said sensed current.