Patent ID: 6236789
Filing Date: 2001-05-22
Classification: G02B,H01B

Abstract:
A composite cable for conveying electrical energy and optical signals to a plurality of electrically energized units which process the optical signals, each of said units having predetermined electrical current and predetermined voltage requirements, the cable having a longitudinal axis and comprising:at least one longitudinally extending plastic buffer tube loosely containing at least one optical fiber for optical signal service to at least two of said electrically energized units, wherein the number of optical fibers is at least two;at least one longitudinally extending layer of a plurality of insulated electrical conductors, wherein said conductors are S-Z stranded in side-by-side relation around said buffer tube to provide a layer of conductors having a radial thickness substantially equal to the thickness of a conductor, wherein a pair of said conductors has a resistance selected so that when the sum of the predetermined current for two of said electrically energized units flows therein, the voltage drop along said pair of conductors satisfies said predetermined voltage, wherein said pair of conductors has a safe current carrying capacity for the current required by said at least two of said electrically energized units and wherein the number of pairs of conductors is less than the number of optical fibers;a plastic jacket encircling the layer of conductors; andat least one strength member extending longitudinally of said cable and disposed inwardly of the outer surface of said jacket.