Telecommunications Power Supply System in the New International Telecommunication Building in Japan

To meet the increasing demands of international telecommunications in Japan, 32-storied building (KDD Building) was constructed in Tokyo in 1974. In order to feed power to the telecommunication equipments, the constant voltage and constant frequency uninterruptible power plant of 4000 kVA which will meet the demand of power consumption required for the future increase of telecommunication equipments was decided to be installed in the basement. AC power generated in this power plant is fed to the telecommunication equipment floors by distribution trunk lines where the AC power is converted into AC or DC power required for each telecommunication equipment. This paper describes the design, configuration and reliability of the telecommunications power supply system (UPS).