The on Line Computer System for the EL4 Nuclear Power Plant

This paper describes the experience and the operation results of computer processing at the EL4 heavy water power plant, in particular: 1) about the hardware, a classification of the most characteristic failures and the unavailability time, 2) about the software, a remodeling of some basic programs, 3) about the plant operation, a remodeling of some automation programs as a result of process and mechanical equipment modifications and evolution of the operation philosophy.