Initial Results of a New Ongoing Study to Monitor Power Line Disturbances and their Affect on Telephone and Computer Systems of the 1980's

Voltage disturbances of all types occur in different geographic areas of the United States. The effects of these disturbances on large computers and data processing centers have been published in studies over the last two decades. This paper will evaluate power line disturbances as they affect today's trends toward distributed power, the proliferation smaller computers and lower operating voltages. The effect of line disturbances upon high-speed, low voltage computers will be studied in selected high-technology sites geographically based toward the west with emphasis on Areas not studied before. The preliminary findings of the first 6 sites will be presented during the 1987 Intelec. The study will continue through 1987 and will monitor additional sites. It is anticipated that first results may be inconclusive, and that data from more sites over a longer period will be needed. The final results of the ongoing study will be presented during the 1988 Intelec meeting if acceptable. Using the BMI 4800 Powersope, the latest technology in power line monitors, the initial results on first 6 sites indicate the primary source of power line disturbance that affect telephone and computer system operation are generated internally to the building. These disturbances may be as high as 70% of the overall power line related disruptions to the telephone and computer systems. The BMI data shows actual pictures and graphs of severe waveshape distortion normal mode (line to neutral) and common mode (neutral to ground) impulses and high frequency noise the power line internal to the building.