Renewal and upgrading of the TRIGA Mark II research reactor in Ljubljana

Despite regulatory supervision, the owner/operator is directly responsible for safe operation of the reactor. Therefore, at the 250 kW TRIGA Mark II research reactor in Ljubljana ever since the beginning of the operation in 1966 gradually modification and modernization have been taking place. During the last twenty years many improvements were introduced, such as: - a dry central thimble for target irradiations (isotope production) - a new pneumatic facility for loading and unloading samples in a new rotary specimen rack or the central thimble - automatic data logging by a configuration based on two microcomputers (already in 1978) - a new analog instrumentation for the nuclear channels, a water level indicator, an integrator (digital power meter) and a reactivity meter - a new spent fuel storage. Further more, it was decided in 1989 to upgrade our reactor for pulsing mode operation and pulse registration. The technical experience that has taken place during the last 25 years was utilized in planning and installing a new control console, and to develop a sophisticated system for the pulse mode operation. (orig.)