High reliability radiation protection control system for fusion device EAST

Three-system-boards redundancy hardware, menu and status machine were developed, to ensure anyone can not enter the area of high radiation in any case, and to stop the potential radiation leakage in time. The measured and controlled objects of the system are environment radiation monitoring network, access control system, fusion operation control system, shielding door pull system, gamma monitor in shield building as well as other facilities. A fault tolerance way of three-system-boards redundancy hardware was designed. The system output variables are still right or at least safety, even if without fault diagnostic circuit, should a fault occur in one system board.