Reliability study of the JET neutral injection system

The JET (Joint European Torus) neutral beam injection (NBI) system, has demonstrated a very high degree of reliability and availability. Data on the reliability and availability of the beamlines and the associated subsystems (e.g. power supplies, cooling and cryogenic supplies, computerized control, etc.) have been recorded over the past three years. These data are used to quantify the overall reliability of the NBI systems and to identify problem areas. The overall reliability (energy injected into JET/energy requested) and availability for the 1990 experimental campaign are both better than 80% and improve significantly during routine operation to nearly 90% after the system has been fully commissioned.<<ETX>>