MAX IV transitioned over to an uninterruptible power supply (UPS) at the end of September to protect the linear accelerator and storage rings from perturbations in the power supply.
The UPS offers instantaneous protection from power outages, and is capable of providing uninterrupted electrical power to MAX IV for 15 seconds with all accelerators in operation.
Power dips to below 90% of the nominal voltage occur, on average, once per 8 days, and a sizeable fraction of these result in beam dumps, and a significant downtime during the recovery. Since the installation of the UPS there have been two instances where the incoming power sagged for up to 100 ms, and no perturbation was observed on any of the accelerators.
Screenshot by Andreas Mattson