Overhead cable

Abstract: The disclosed telecommunication overhead cable distribution system 10 includes a plurality of "T"-shaped distribution units 20 that are located at desired distribution locations. A plurality of cable support sections 22 extend, protect, and support the telecommunication cables between the distribution locations. Each section includes a plurality of identical support units 24 that are releasably interconnected to each other. Each unit is pivotable about a horizontal intra-unit axis "A" and about an inter-unit vertical axis "B". Each unit is comprised of a female member 26 and a male member 28 in which the male member is releasably interlocked with an adjacent female member. Such a system provides for a system having a minimum of components with a maximum of versatility. The ends of the section 22 fit into receptive cavities formed in the "T"-shaped distribution units 20.

Abstract: An improved cable paying out and taking up device particularly for use in underground or overhead cable pulling environments which includes a novel winch assembly disposed on a vehicle, a swivel fairlead disposed on a trailing portion of the vehicle bed adapted for facile removal and redeployment, the swivel fairlead provided with instrumentalities for operatively orienting a pulley sheave associated with the fairlead in 360° of direction and allowing disassociation of the pulley sheave from its associated support drum so that cable including an enlarged end unable to fit within clearances about the pulley sheave can be threaded through the swivel fairlead without disassociation of the cable from the enlarged end. The novel winch briefly includes a pair of winches modified to accommodate a removable bull wheel having a plurality of grooves on its outer face, the grooves dimensioned to receive cables corresponding to the diameter of the cable, an instrumentality for assuring level winding, a pressure responsive instrumentality associated with a reel to accommodate variations in effective reel diameter due to cable build-up and pay-out, so that hydraulic pressure and synchronization of the various rotating winches and reel can be coordinated for the accurate functioning of the apparatus.

Abstract: A composite overhead cable structure for electric and optical transmission comprising a pipe, at least one layer of stranded metallic elongated conductor surrounding the outer periphery of said pipe in close contact with said outer periphery, and an optical fiber cable tightly disposed within and extending throughout the length of said pipe through the medium of a packing comprised of at least one double packing layer of a non-metallic soft packing layer and a non-metallic rigid packing layer, thereby providing fixed package of said optical fiber cable in said pipe through said packing so that said optical fiber is unmovable relative to said pipe. With such a structure, the optical fiber cable is effectively prevented from not only occurrence of local bending or, but also from suffering excessive lateral forces, which leads to elimination of a danger that the optical fiber be damaged, thereby enabling the optical transmission properties to be stably maintained.

Abstract: Heavy fault currents flow in the event of fault at the loads connected in distribution system. To protect these loads, circuit breakers and relays are required at appropriate places with proper coordination between them. This research paper focuses on finding optimum relay setting required for minimum time to interrupt power supply to avoid miscoordination in operation of relays and also investigates effect on time multiplier settings (TMS) of directional overcurrent relays in a system with combined overhead lines-underground cables. Linear programming problem (LPP) approach is used for optimization. It is interesting to know the quantitative variations in TMS as the underground cables have different characteristics than overhead lines.