Ericsson Energy Systems (Sweden) unveiled new high efficiency BZA 131 70 battery-backed dc power system at the recent Intelec Conference in Copenhagen. The BZA 131 70 offers up to36kW of -48Vdc power with associated distribution and protection in a single ETSI standard cabinet. As well as providing high power density, the integration of the rectifiers in the power cabinet significantly reduces the time and cost of installation and commissioning. The advanced design needs no external power factor correction, and has been developed with less than 10 percent THD to meet the anticipated IEC 950 regulations on mains pollution. Following successful initial installations Ericsson expects to begin world wide deliveries of the BZA 131 70.The modular BZA 131 70 is easily expandable as requirements grow, and includes a full range of protection, battery, ac and dc distribution options, as well as four different sizes of 600mm wide ETSI standard cabinets. with a choice of rectifiers specified for use with either 310V to 520V at 45 to 65Hz or 190V to 288V at 45 to 65Hz input. These flexible systems are designed to work anywhere in the world and even be earthquake protected. The BZA 131 79 is designed to be a complete power solution for 48V protected equipment, intended for use in a wide variety of applications, such as telephone exchanges, Internet services and satellite links. The BZA 131 70 is claimed to reduce cost of ownership by delivering more than 91 percent efficiency, and near unity power factor at 0.97. The intelligent distribution options include transient limiting versions, and in common with all other sub-systems communicate alarms and data via interference-free optical fibers to the central supervision unit. the unit provides both a local display and an RS422 communications for remote monitoring and control.