Abstract :
THE original basis for the selection of 1.4 inches as the diameter of the conductor for the Boulder Dam transmission line was provided principally by test data taken at the Ryan High Voltage Laboratory, at Stanford University, by the Department of Water and Power in co-operation with Doctor Joseph S. Carroll, on conductors ranging from 1.125 inches to 2 inches in diameter.1 Also reference was made to other previous corona work at the same place.2,3,4 An analysis and use of the data,5,6 taking into account temperature and altitude effect and making some allowance for unknown factors affecting corona laws that had appeared in many of the tests, led to the final recommendation of 1.4 inches as the diameter for the conductor for 287.5 kv.