Applying HID high-pressure sodium lamps in a variable-voltage environment

This paper presents the results of laboratory tests to determine the effects of voltage sags, interruptions, and fluctuations on high-pressure sodium (HPS) lamps and ballasts. The way these ballasted lamps react to sags and interruptions in the laboratory is then compared to a model of the real-world electrical environment created from data gathered during three North American power quality surveys. This work also shows how HPS immunity to voltage variations depends significantly on the ballast type and the lamp age.