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[en] The original analogue vibration monitoring system of the Steam Turbine Generator Line in Angra 1 Nuclear Power Plant had become obsolete and it was difficult to find spare parts. ELETRONUCLEAR decided to have a new digital system to substitute the original one and to provide automatic warning and prediction of developing faults. The new system was specified by the plant supporting group together with the plant engineers. It was installed to measure shaft and bearing vibrations, absolute and relative expansions as well as bearing and oil temperatures. It performs auto diagnosis, automatically interpreting all condition monitoring data to reveal and warn the staff about potential faults under development. Advanced condition monitoring may help revealing potential risks, making it possible to plan corrective actions at the scheduled production stops for safety inspections. The main goal is to increase the reliability of the production by identifying machinery problems in an early development stage and by providing the organization with information to increased safety. Already during the initial implementation phase valuable conclusions could be made for several issues such as misalignment, bearing tolerances, imbalance and bearing rub. The information directs inspections to those parts of the machine that really need it and avoids inspections where it is not required. This typically minimizes scheduled downtime for maintenance work. The system issued an automatic auto diagnosis warning about a short rub of a journal bearing during a coast down. The machine is designed to deal with these types of rub, but they should not happen repeatedly. The operators have to know about these rubs in order to conduct further analysis to determine the seriousness for future maintenance activities. The system informs whether any rubs occur, enabling them to judge whether they need to make an inspection at the next planned outage. This means, in other words, pro-active maintenance instead of re-active. (author)''