Volume 1 of this book is a compendium of a state of art of the protection systems in the conventional HVAC networks. The main chapters are dedicated to generators, transformers, lines, feeders and busbars protections, complementing them with all the necessary theories for an accurate analysis. Special emphasis has also placed on the analysis of electrical phenomena associated with protections, such as short circuits and the effect of high-frequency transients. In addition some testing case studies are also described emphasizing practical considerations that may affect tests that are typically defined for some devices.