Some Aspects and Experiences Regarding Centralized/Decentralized Power Supply Systems in the Swedish Telecommunications Network

For some years the advantages and disadvantages of using centralized or decentralized power systems for telecom equipment have been discussed. The major topic has been the philosophy for powering the switching equipment. The question has been whether a large centralized DC power system or a decentralized rectifier system with a common battery bank, or a fully decentralized power system integrated into the switching equipment should be used. As in many other Administrations and operating companies Televerket's network needs switching, transmission, data and radio equipment from different manufacturers for its operation. The major part is designed for DC powering but much of it requires AC power input. When working together in the telecom network all the different types of equipment have to be functionally matched. Furthermore a great deal of consideration must be given to the general powering principles such as earthing, safety and coordination of reserve time. This paper intends to define some of the conditions mentioned and will also give some examples of how these problems are dealt with in Sweden.