Patent ID: 6141192
Filing Date: 2000-10-31
Classification: H01H,H02H

Abstract:
An arcing fault protection system for a switchgear enclosure accommodating a plurality of feeder circuits, each of said feeder circuits being electrically connected to a source bus and carrying an electric current through said switchgear enclosure toward one or more loads downstream of said switchgear enclosure, said source bus being connected to a power source through a main circuit, said switchgear enclosure including a plurality of compartments for housing electrical components associated with said feeder circuits, said arcing fault protection system comprising:a current sensor for monitoring said main circuit for the presence of arcing fault currents;a plurality of optical sensors for monitoring said feeder circuits for the presence of arcing fault currents;means for producing an arcing fault detection signal in response to said current sensor detecting said arcing fault currents in said main circuit and at least one of said optical sensors detecting said arcing fault currents in an associated one of said feeder circuits; anda grounding device for rapidly grounding said source bus in response to the production of an arcing fault detection signal by said protection system, the grounding of said source bus diverting current carried on said source bus to ground and rapidly eliminating arcing fault currents occurring on any of said feeder circuits; wherein said grounding device comprises to switching means for operating in less than about 4 milliseconds following the occurrence of an arcing fault.