Power quality study-1990 to 1995-initial results

The 1990-5 National Power Laboratory (NPL) power supply quality study has accumulated 450 site-months of power line disturbance data. At this time, the database exceeds the combined collected databases of the widely quoted IBM (1969-72) and AT&T (1977-9) power studies. The scope and magnitude of the NPL study are discussed. Initial results are presented based on 450 months of the eventual 1800 site-month database. These initial results indicate that a typical site will have 443 power disturbances outside of the computer manufacturers standards for power quality. Recommendations are made for the use of power conditioning and protective equipment to protect critical loads