Continued Investigation of Arc Flash in Single Phase Systems

IEEE 1584 - 2018 documents the standard method for calculating arc flash incident energy. This value is then used to establish one of several safety boundaries around exposed, energized electrical conductors and to select protective equipment. While 1584 covers three-phase configurations in detail, it currently excludes single-phase calculations. Prevalence of single-phase AC power distribution inspired curiosity about possible hazards of fire and injury arising from arc flash in such systems. This paper extends work previously published and covers the conclusion of doctoral research into single-phase arc flash in one laboratory configuration. Further experimental work supported the hypothesis that incident energy would be low (less than 1 cal/cm2) for single-phase events below some threshold voltage and for available fault currents up to 22,000 amperes. This threshold voltage appears to be near 434VAC. Repeated test groups at greater than 434V sustained the conclusion that such configurations develop dangerous levels of heat and blast pressure even when the source is single-phase.