Design of the Accelerator Safety Interlock System for the XFEL in SPring-8
C.Saji, M.Kago*, N.Nariyama, R.Tanaka, T.Matsushita (JASRI/SPring-8) T.Fukui, T.Itoga, Y.Asano (RIKEN/SPring-8)
The X-ray Free Electron Laser (XFEL) Facility in SPring-8 is now under construction. The accelerator safety interlock system for the XFEL is required for protecting persons from radiation hazard. The system consists of three interlock systems; a central interlock system (CIS), an emergency interlock system (EIS) and a beam-route interlock system (BIS). The CIS monitors the safety equipment status. The EIS monitors status of emergency stop buttons. The BIS monitors consistency between the predefined electron beam route to the downstream insertion devices and the actual transport route by inputting the current of the bending magnet at the beam switching points. If the condition is unsafe, these systems don't give the permission to the accelerator operation and stops the electron beam. The programmable logic controller (PLC) is basically used to control of each interlock system. It is required to stop the electron beam within 16.6ms because the design maximum repetition frequency of the electron beams is 60Hz. Therefore, we developed the optical module that can transmit high-speed stop signals. We report the present status of accelerator safety interlock system for the XFEL.