The book presents a description of novel technology for protection of high-voltage equipment (power supplies, lasers, radar and RF generators) against internal breakdowns and overloads, and also for upgrading of automation systems in 10- to 36-kV power networks. The book contains technical details essential to manufacturers of high-voltage equipment for commercial production of protection devices and to power companies for self-supporting building the devices in their laboratories. This book discusses general problems related to the generation of current overload protection systems; describes different designs of new type high-voltage interfaces; describes the high- and low-voltage semiconductor and reed switch-based hybrid switching devices; and contains vast ready-reference information intended to facilitate designers reproducing the described devices. To whom does it point? The book suited to electrical, radio, power, electro-physical, industrial engineers; research and development managers; and upper-level undergraduate, graduate, and continuing-education students in respective disciplines. Lecturers of colleges and instructors of training courses in the respective subjects will find in the book interesting reference material for lectures.