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A number of electron cyclotron codes have been developed in di erent Eu- ropean laboratories, to describe the behavior of EC waves in realistic tokamak plasma scenarios, and to optimize EC heating and current drive e ciency in present, and future devices like ITER. Moreover, integrated modelling is gaining popularity, since it seems to be the optimum approach for modelling tasks as complex as the assessment of future large devices performances. The outcome is presented here of a benchmark exercise for a set of EC codes, performed within the framework of the European Integrated Tokamak Mod- elling Task Force, and based on a standard ITER scenario, considering multiple launching conditions of the EC waves. The advantages o ered by integrated modelling are explored and exploited, and the sources of the small-but-still-present di erences among the various codes results are investigated.

Electron Cyclotron Resonance Heating (ECRH) systems for next step-fusion devices like W7-X and ITER operate in CW-mode and provide a large flexibility to comply with various physics demands such as plasma start-up, heating and current drive, as well as configuration and MHD control. The request for many different sophisticated applications results in a growing complexity of the systems. This is in conflict with the request for high availability, reliability, and maintainability, which arises from DEMO demands. 'Advanced' ECRH-components must, therefore, comply with both the complex physics demands and operational robustness and reliability. The W7-X ECRH system is the first CW facility of an ITER relevant size and is used as a test bed for such components. Results on improvements of gyrotrons, transmission components and launchers are presented together with proposals for future developments. © 2011 American Institute of Physics.