Engineering Analysis of Possible Effects of 2017 NESC Change Proposal to Remove 60' Exemption

McCall-Thomas Engineering is pleased to present the results of the study to determine the possible effects of the 2017 NESC code change proposals being reviewed by the Subcommittee 5 to remove the 60' Exemption. This document provides details on the study assumptions, methodology, and findings. Five lines were considered the base standards for the project and represent single and three phase designs existing on cooperative systems. These examples were examined, the 60' Exemption was removed and the proposed wind and ice loading requirements were analyzed. Any changes required were documented and a cost analysis was generated.; Base Line Designs- 1-phase #2 ACSR, 1-phase #1/0 ACSR,3-phase #336 KCMIL ACSR, 3-Phase #477 KCMIL ACSR, Secondary Triplex; Additional Pole Loading - The 3-Phase #477 KCMILACSR example and the 1-Phase #1/0 ACSR examples werealso analyzed adding the following additional loads: One Cooperative Fiber One foot below the Neutral; One Telephone Joint User; One Telephone and One Cable Joint User; One Cooperative Fiber, One Telephone and One Cable Joint User.; Each design was analyzed for medium loading district, 15 psf Grade C, 15 psf Grade B, 15.5 psf, 18 psf, as discussed in the 2017 NESC pre-print.