Fast Interlock System for Machine Protection in PLS-II

We overview the system design of the Pohang Light Source-II (PLS-II), and demonstrate that synchrotron radiation is the cause of a recent incident that damaged the vacuum components. To preclude further incidents, we designed a system that shuts off the beam if such damage is imminent. We used an ANSYS simulation to estimate the appropriate time allowed for this shut-off then. A Fast Interlock System is implemented to accomplish beam shut-off within this time. In bench test, this system shut down the beam within the acceptable time. The installation and the operation of the Fast Interlock System in PLS-II is planned.