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The new superconducting Linear Coherent Light Source (LCLS-II) at the SLAC National Accelerator Laboratory will be an upgrade to LCLS, the world’s first hard X-ray free-electron laser. LCLS-II is in an advanced stage of construction with equipment for both Cryoplants as well as more than half of the 37 cryomodules onsite. Jefferson Lab (JLab) is a partner lab responsible for building half of the LCLS-II cryomodules. Hence the Low Energy Recirculation Facility (LERF) at JLab was used to stage and test LCLS-II cryomodules before shipping them to SLAC. LERF was set up to test two cryomodules at a time. LERF used LCLS-II cryogenic controls instrumentation racks, Programmable Logic Controllers (PLC) controls and Experimental Physics and Industrial Control System (EPICS) Input/Output Controllers (IOCs) with the intention to use the LERF setup to check-out and verify cryogenic controls for LCLS-II. The cryogenic controls first utilized at LERF would then be replicated for controlling all 37 cryomodules via an EPICS user interface. This paper discusses the cryogenic controls currently developed for implementation in the LCLS-II project., Proceedings of the 17th International Conference on Accelerator and Large Experimental Physics Control Systems, ICALEPCS2019, New York, NY, USA

The JLab Low Energy Recirculating Facility, LERF, has been modified to support concurrent testing of two LCLS-II cryomodules. The cryomodules are installed in a similar fashion as they would be in the L1 section of the LCLS-II linac, including the floor slope and using all of the LCLS-II hardware and controls for cryomodule cryogenics, vacuum, and RF (SSA and LLRF). From the start, it was intended to use LCLS-II electronics and EPICS software controls for cryomodule testing. In affect the LERF test facility becomes the first opportunity to commission and operate the LCLS-II LINAC hardware and software controls. Support for specific cryomodule high level test applications like Q₀ and HOMs measurements, are being developed from the basic cryomodule control suite. To support the testing, 2 K He is supplied from the CEBAF south linac cryogenic system, where care must be taken when using the LERF test facility to not upset the CEBAF cryogenics plant. This paper discusses the commissioning of the hardware and software development for testing the first two LCLS-II cryomodules., Proceedings of the 19th International Conference on RF Superconductivity, SRF2019, Dresden, Germany

LCLS-II is a superconducting upgrade to the existing Linear Coherent Light Source at the SLAC National Accelerator Laboratory. Construction is underway with a planned continuous wave beam rate of up to 1 MHz. Two cryogenic plants provide helium to a distribution system, and 37 cryomodules with superconducting cavities will operate with Liquid helium at 2.2K. The cryomodules and distribution system is controlled with networked PLC's and EPICS as an integrated system that work in concert for controlling valves, pressure, flow, and temperature. Interlocks and critical process information is communicated with the Low Level Radio Frequency, vacuum, and magnet systems. Engaging the controls community proved vital in advancing the controls architecture from a conventional design to a centralized, reliable, and cost-effective distributed platform., Proceedings of the 16th Int. Conf. on Accelerator and Large Experimental Control Systems, ICALEPCS2017, Barcelona, Spain

The Klystron Bake Station at SLAC is a facility for baking out klystrons (high power RF amplifiers) among other equipment in preparation for installation in the linac. The scope of this project was to upgrade the 30 year old controls (based on VMS and CAMAC) to utilize PLC automation and an EPICS user interface. The new system allows for flexible configuration of the bake out schedule which can be saved to files or edited real time both through an EPICS soft IOC as well as a local touch panel HMI. Other improvements include active long term archiving of all data, COTS hardware (replacing custom-built CAMAC cards), email notification of fault states, and graphical user interfaces (old system was command line only). The first station upgraded came online in November 2016 and two more stations are planned to follow this year. Year poster discusses the improvements made and problems encountered in performing the upgrade., Proceedings of the 16th Int. Conf. on Accelerator and Large Experimental Control Systems, ICALEPCS2017, Barcelona, Spain