Patent ID: 7403129

Claim:
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.