Noise Rating Method for Fluorescent Lamp Ballast Transformers

Abstract

The noise radiated from a composite fluorescent lamp system (ballasts, lamps, fixtures, and supporting structure) is dependent to some degree upon the physical and geometrical characteristics of all components. Analytical representation of the composite continuum is inhibited by many difficulties, not the least of which is the wide variation in the various composite systems that can occur. However, the mechanical impedance concept presents a powerful tool for systems of this type where selected measurements can be performed to greatly reduce the analytical effort. Theory is presented to analytically represent the composite system in terms of mechanical impedance. Measurements utilizing a force sensor were made for a number of ballasts which yield information useful in the general theory. A rating method was devised for the ballasts, independent of the rest of the system, which compares their noise-generating capabilities. The method is based upon the measured results of over-all force levels increasing monotonically with input electrical power. (This research was sponsored by Sola Electric Company.)