The Design and implementation of diagnostic systems on ITER

Costley, A. E.*; Walker, C. I.*; Bertalot, L.*; Barnsley, R.*; Itami, Kiyoshi; Sugie, Tatsuo; Vayakis, G.*

In order to meet the needs for first wall and plasma measurements, ITER will require about 40 different diagnostic systems drawn from all the main generic diagnostic groups - magnetics, neutron systems, optical and microwave systems, spectroscopic, bolometric, probes, pressure gauges and gas analysers. The design and implementation is a major challenge because of the harsh environment in which many of the diagnostic components are located coupled with the restricted access and the need to meet stringent engineering requirements arising from the fact that ITER will be a nuclear device. It has stimulated an extensive design and R&D programme and the development of some novel approaches to diagnostic installation: for example, the use of plugs with custom modules at the upper and equatorial levels that serve both to support the diagnostic components and to provide the necessary shielding of the neutrons. The difficulties of implementation are summarized and the novel solutions described.