Optical Cable Suspension Cable Process

The optical cable suspension process involves careful route planning, pole selection, tensioning, and the use of suspension clamps to safely support aerial optical fiber cables while minimizing stress and strain on the fibers.Route Survey and PlanningBefore installation, the aerial route must be surveyed pole by pole to identify obstacles such as roads, canals, or electric lines. A line diagram is prepared marking pole locations, distances, and potential splicing points. For new routes, alignment is erected with a maximum span length typically not exceeding 90 meters, and additional poles are added in hilly regions or sharp curves to prevent excessive bending or stress on the cable .Pole SelectionTension Poles: Every fifth pole in a straight alignment or at sharp turns (over 15 degrees) is designated as a tension pole to handle the main pulling forces .Suspension Poles: Intermediate poles between tension poles act as suspension poles, providing cushioning against dynamic stresses like Aeolian vibration and reducing static stress at support points .Cable Handling and InstallationTension Pay-Off Method: The cable is paid off under controlled tension to keep it suspended and prevent abrasion against the ground. Proper tension reduces physical labor and ensures smooth installation .Suspension Clamps: Clamps such as HUBRPXSUS or FlexNAP system clamps are used to secure the cable to poles. The clamp must be oriented correctly, with the eyehole aligned to the cable direction, and tightened to the specified torque (e.g., 15 ft/lb) without over-torquing .Bend Radius and Pulling Force: The cable should not be bent beyond its minimum recommended radius, pulled with excessive force, or crushed, as this can damage the optical fibers and impair signal transmission .Splicing and Joint LocationsSplice boxes are positioned overhead according to the cable drum length. Proper planning ensures that splicing locations are accessible and that the cable length between poles accommodates the required slack for thermal expansion and mechanical stress relief .Safety ConsiderationsInstallers must follow all relevant safety codes, including the National Electrical Safety Code (NESC), and use personal protective equipment such as helmets, safety belts, and warning signs. Laser light from active fibers can be invisible and harmful to the eyes, so direct viewing must be avoided .Cable Types and SpecificationsSelf-Supporting Metal-Free Cables: Suitable for short-haul or local junctions where underground installation is not feasible .OPGW Cables: Contain optical fibers within a protective metal sheath, often combining stainless steel and aluminum for corrosion resistance and mechanical strength . Loose tube construction prevents fiber strain during installation.SummaryThe optical cable suspension process is a combination of careful route planning, proper pole selection, controlled tensioning, and secure clamping. Following these steps ensures the cable remains mechanically stable, minimizes fiber strain, and maintains signal integrity throughout its operational life. Proper safety practices and adherence to manufacturer specifications are critical for successful installation.