The diagnostic system of the Neutral Beam Injectors for ITER heating and current drive

The RFX reversed field pinch (RFP) has undergone major modifications of the load assembly and is now equipped with a large number of active external coils for magnetohydrodynamics mode control. The study of the effects on the plasma of both the new passive structure and the active coils is then of great importance, as well as the investigation of turbulence due to its influence on plasma transport. An integrated system of magnetic, electrostatic and calorimetric sensors has been realized, fulfilling very challenging requirements in terms of spatial and temporal resolution, which are characteristic features of RFP plasmas. A description of the whole diagnostic system is given, including the original solutions adopted to cope with the limited space available and the thermal and electrical requirements, particularly for the calorimetrical probes. The tests performed on the whole system during the installation are presented. Signal conditioning and data acquisition are described.