Aerial Laying

Service Details

Prior to beginning an aerial cable installation, careful planning and preparation are necessary. Representatives of each organization potentially affected by the installation (utilities, street department, police, etc. ) should be present during the route survey. Approval by all necessary parties should be secured before detailed planning begins. A few of the issues to be considered are listed in the following paragraphs. Planning should be undertaken jointly by construction and engineering personnel. Hardware requirements should also be considered at the planning stage.Route Planning, Pole Selection and Authorization Determine the ability of existing pole lines and guys to support the new cable, as well as any restrictions imposed by the pole owner. The anchoring and guying of the cable is crucial for its safe operation. Ideally, the guying should remove all of the lateral stress on each pole so that the pole simply supports the weight of the cables, hardware and equipment attached to it. Your company’s normal specifications concerning anchoring and guying of poles should be followed.Cable Reel Care and Inspection Leave the protective covering on the reel intact until it arrives at the installation site. Upon removal of the protective covering, inspect the cable jacket for signs of damage. If the covering has been previously removed, secure the cable end(s) during transit to prevent damage. Cable reels should be stored vertically on their flanges and chocked to prevent rolling. Determine if your company requires that the cable be tested for optical continuity prior to installation. These tests can be done with an Optical Time Domain Reflectometer (OTDR) to verify length and attenuation uniformity. During installation, periodically inspect the reel to ensure that the through-bolts do not loosen. Tightening them will ensure that the cable pays off the reel correctly.Minimum Bend Radius Excessively sharp bends can damage fibers within fiber optic cables. The minimum bend radii for both tensioned and no-tension conditions are on the cable specification sheet. As a general rule, the minimum bend radius for a cable under tension is 15 times the nominal outside diameter of the cable. The minimum bend radius for cables not under tension is 10 times the nominal OD of the cable.Figure-eighting Figure-eighting can be used in order to pull in both directions from a central location or to make a transition from the moving reel (drive-off) installation method to the stationary reel installation method. This makes it possible to use the relatively quick and uncomplicated moving reel technique on that portion of a cable route accessible by vehicles and the more involved stationary reel method where vehicle access to the pole line is not possible. Whenever cable is unreeled for subsequent pulling, it should be coiled in a “figure-eight†configuration. This procedure will prevent damage due to twisting of the cable. This figure-eight coil should measure at least 9 m by 5 m (30 ft by 15 ft) and be protected from passersby.Laying Determine the cable reel and pull locations, each of which can be at any point along the route. The location of the cable reel and any subsequent intermediate pull points must be determined during the route survey. Some of the factors to consider are: