Accurate ampacity determination: temperature-sag model for operational real time ratings

This report presents a method for determining transmission line ratings based on the relationship between the conductor's temperature and its sag. The method is based on the ruling span principle and the use of transmission line tension monitoring systems. The report also presents a method of accurately calibrating the final sag of the conductor and determining the actual-ruling span length of the line sections between deadend structures. Main error sources for two other real time rating methods are also examined. >