POINT OF UTILIZATION POWER QUALITY STUDY RESULTS

A wide variety of electromagnetic phenomena occurring on ac power line s has been held responsible for literally billions of dollars per year in lost revenue. Information related to actual probability of occurre nce of these power line deviations is presently limited. This paper de scribes the results of four years of point of utilization power qualit y monitoring at 112 North American locations. A quantity of 1057 site months of data collected between 1990 and 1994 was used in this assess ment. The data indicate that the numbers of events occurring at typica l locations may range from almost none, to thousands per month. The an alysis results characterize several aspects of power quality related t o the occurrence of low rms events, high rms events, transient events, and power interruptions (outages).