Patent ID: 6801117
Filing Date: 2004-10-05
Classification: H02H

Abstract:
An apparatus for sensing over-temperature and mechanical damage in electrical wiring, comprising:at least one fault-sensing electrical wire comprising an electrical conductor surrounded by insulation and at least one sensor strip disposed in said insulation along substantially the length of said wire, said at least one sensor strip spaced apart from said conductor by a strip separation space said at least one sensor strip performing a temperature-responsive function and a mechanical damage-sensing function, said temperature-responsive function provided by use of a material in said at least one sensor strip having a positive temperature coefficient of resistivity which increases with temperature and said mechanical damage-sensing function provided by including a portion of said at least one sensor strip disposed between said conductor and an outside surface of said wire so that mechanical damage to said insulation severs said portion of said at least one sensor strip before said conductor is exposed; a control unit responsive to the impedance of said at least one sensor strip, said control unit providing a first control signal responsive to a first thermal condition of said at least one sensor strip and a second control signal responsive to severance of said at least one sensor strip; and an arc sensor comprising a circuit configured to sense a current flow across said strip separation space.