Nomographic Computation of the Ampacity Rating of Aerial Conductors

Abstract

The prime objective is to develop a comprehensive and explicit method for computing the current-carrying capacity for either bare, covered, or iced aerial conductors. There have been many methods devised to compute ampacities. Moreover these methods are often quite involved and require the use of computers for their solution. The nomographic process encompasses more complex situations. It operates on the complicated nature of these formulations in a manner that reduces their complexity to a simple, accurate, and hence efficient system of computation. Intentionally, there is a vast amount of versatility built into this procedure whereby many ampacity-related parameters, for example, conductor temperature or wind velocity, may be computed easily and quickly. This development is designed to assist the reader in exploring the complete panorama of parameters or variables that manifest themselves in the science of current rating rather than in portraying a procedure needed to compute only ampere values. Furthermore, it is intended that computer programs would be used to solve problems involving a multitude of conductor sizes and/or ambient conditions, whereas the nomographic approach would, in essence, provide an analytical tool that can be drawn upon for the purposes of solving isolated ampacity problems.