Electrical surge protection devices for industrial facilities - a tutorial review

Industrial facilities are becoming more and more dependent on computer control of their processes and as a consequence require an increase in cleanliness and reliability of the electrical power supply system. Electromechanical subsystems are being replaced by electronic logic. Harmonic interference, welding, variable speed drives and other "in plant" noise have reliable mitigation procedures. However, lightning and other external sourced power disturbances rank high on the list of "uncontrollable" events that have shut down facilities in recent years. This paper provides an overview of the causes of power line surges and their consequences for an industrial plant. The relevant international surge protection standards is briefly reviewed and their differences are analyzed. Different technologies utilized in the implementation of various commercially available surge protection devices are presented, followed by a comparative analysis. Finally the latest trends and the most promising technologies in surge protection systems, as well as their ability to overcome the problems associated with conventional protection devices are overviewed and experimental data based on field trials are reported.