Ericsson Power Systems, a division of RIFA AB, has, in collaboration with the Swedish Telecommunications Administration, developed and put into operation a computerized system for the supervision of energy equipment in telephone exchanges. The system, ERICSSON ENERGY-MASTER (EEM), allows centralized control of all energy equipment in a maintenance area, resulting in improved operating economy and greater reliability. EEM is a further development of Ericsson's previous system for processor control of power supply equipment (1).