Magnetic compatibility of standard components for electrical installations : Computation of the background field and consequences on the design of the electrical distribution boards and control boards for the ITER Tokamak building.

Inside the proposed Tokamak building, the ITER poloidal field magnet system would produce a stray magnetic field up to 70mT. This is a very unusual environmental condition for electrical installation equipment and limited information is available on the magnetic compatibility of standard components for electrical distribution boards and control boards. Because this information is a necessary input for the design of the electrical installation inside the proposed ITER Tokamak building specific investigations have been carried out by the ITER European Participant Team. The paper reports on the computation of the background magnetic field map inside the ITER Tokamak building and the consequences on the design of the electrical installations of this building. The effects of the steel inside the building structure and the feasibility of magnetic shields for electrical distribution boards and control boards are also reported in the paper. The results of the test campaigns on the magnetic field compatibility of standard components for electrical distribution boards and control boards are reported in companion papers published in these proceedings.