Inductive Static Eliminators: Methods of Efficiency Measurement

Inductive static eliminators neutralize a charged surface with ions emitted from a corona discharge. The discharge is initiated by the field induced at the eliminator as a consequence of its close proximity to the charged surface itself. Several types are made commercially, with metallic tinsel the most common. From first principles, analytical and experimental techniques were developed to characterize an eliminator´s efficiency. Efficiency is defined in terms of breakdown voltage, discharge time and area coverage. Both theory and experiment indicate a discharge limit of 0.1 to 0.2 nC/cm2. While this is about an order of magnitude less discharge than that obtained with powered eliminators, experience has shown this to be adequate for many applications. The development of the measurement techniques by which we have been able to characterize various inductive eliminator designs is discussed.