Lightning Experience on 132-Kv Transmission Lines of the American Gas and Electric Company System 1930-1931

This paper, which is a continuation of a four-year operating record of an extensive 132-kv transmission system under lightning conditions, presents and discusses the record for 1930 and 1931. Operating experience is given on: 1. Yearly line outages due to lightning for all lines. 2. Severity and frequency of lightning storms over the system for a three-year period. 3. Frequency of double circuit outages. 4. Extent of line and station apparatus damage. 5. Effect of tower footing resistance in reducing lightning outages. 6. Reduction in tower footing resistances by the use of driven ground rods and counterpoises. 7. Effect on lightning outages by overinsulation. 8. Relative frequency of single-phase, two-phase and three-phase line faults. 9. Location of lightning flashovers on the line in reference to top, middle and bottom conductors. Conclusions are drawn from the results of the operating experience on these lines.