Roles of ESD played in large computing system availability & reliability

Product ESD testing per CISPR test requirements specifies direct and/or indirect ESD injection to the outside of the chassis of the product under test or to a vertical or horizontal coupling plane. In this paper additional ESD testing to insure customer satisfaction with large systems is discussed. Two additional ESD test methods are discussed with test locations internal to the normal external shield. First, the application of ESD during manufacturing process is intended to find product defects in order to increase field reliability. Second, internal system testing is intended to mimic potential problems from concurrent maintenance in order to insure system availability during system repair actions without impacting system availability for continuous customer usage.