Most fiber optic cable is designed to conservatively allow a maximum of 1800 N- 4500 N (400 lbf-1000 lbf) of pulling tension during instal- lation. On the other hand, it is desirable to install the longest lengths of uninterrupted cable possible. A dielectric aramid yarn is used, typically by stranding it around the optical fiber cable core, providing the necessary tensile strength for aerial applications. For example, a heavy-duty armored outside plant cable handles much higher tension than a delicate. For cable equipped with pulling eye or pulling bolt, the formula shown below is used to calculate the maximum allowable pulling tension on the cable for the entire routing. The maximum length of cable that can safely be pulled through conduit is calculated as shown below. SpanMaster software takes the user through a logical step-by-step process of information entry and produces sag. While excessive pulling tension can have a negative impact on the integrity of a cable, the Side Wall Pressure (SWP) is a more important factor in cable pulling damages.
