Off-line switching rectifier for energy plant

Towards the end of the seventies, given the introduction of electronic telephone exchanges, energy plants equipped with off-line switching rectifiers were designed and put in service. The range of energy plants dedicated to telecommunication equipment constituted a complete line of unit-composed energy plants named HF 87 and having a power up to 60 kW. The authors describe the principle of these energy plants and their rectifiers, discuss their main features, and present the availability data. It is concluded that the top-level performance, high power/volume rates of modular units and the MTBF (mean time before failure) and MTTR (mean time to removal) values obtained make the energy power plants equipped with off-line switching rectifiers the best solution to the requirements of new telecommunication systems