Wire and cable update-1990

The authors address progress and trends in cable designs, applications, and installations. While medium-voltage cable is emphasized, certain types of low-voltage cable are also considered. Improvements in materials and design are discussed for each component part of the cable including the conductor, semiconducting shields, insulation, metallic shield, and protective jacket. Industry standards are considered as they relate to the proper sizing, rating, and construction of cables used in the petrochemical industry. Ampacity tables for medium-voltage as well as low-voltage cable continue to be a controversial issue, and the authors consider the alternatives covered by the 1990 National Electrical Code (NEC). The 1990 NEC still allows industrial users to calculate technically correct ampacities under engineering supervision. IEEE efforts to establish new and comprehensive methods for determining ampacity are also reviewed