This article offers a variety of descriptive explanations about various surge protection subjects including MOVs, incompatibilities, neutral earthing, dispersion and the role of SPDs.

As surge protection manufacturers continue to bring greatly improved and safer products to market, the testing and certification process for these products has become increasingly complicated, time consuming and expensive as a result of ever-evolving codes and standards. These requirements are proving extremely difficult for some manufacturers to meet in the current economic climate. As a result, many manufacturers of surge protective devices (SPDs) are opting to go to market without a UL listing on their products.