Sag Requirements for Optical Cable Lines on Power Poles

Every span must be analyzed for the size of messenger, the tension required for the span length and cable weight to meet sag requirements. Clearance requirements for aerial cables are defined in Section 23 of the National Electrical Safety Code® (NESC®). Additionally, some countries outside of the United States have adopted all or part of this code. Common terms used in sag and tension calculations are explained below to promote understanding when interp ting the results. This includes separation. ADSS (All-Dielectric Self-Supporting) cable is the standard choice for aerial fiber deployment on power line towers and utility poles — but only when correctly specified. The code in effect across most of the country right now is the 2023 National. National Codes will specify the range of load conditions that poles and their attachments will be exposed. [pdf]