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After 3 years of operation, the LHC entered its first Long Shutdown period (LS1), in February 2013 [1]. Major consolidation and maintenance works are being performed across the whole CERN’s Accelerator chain, in order to prepare the LHC to restart at higher energy, in 2015. The injector chain shall resume earlier, in mid-14. We report about the on-going vacuum-controls projects. Some of them concern the renovation of the controls of certain machines; others are associated with the consolidations of the vacuum systems of LHC and its injectors; and a few are completely new installations. ue to the wide age-span of the existing vacuum installations, there is a mix of design philosophies and of control-equipment generations. The renovations and the novel projects offer an opportunity to improve the uniformity and efficiency of vacuum controls by: reducing the number of equipment versions with similar functionality; identifying, naming, labelling, and documenting all pieces of equipment; homogenizing the control architectures, while converging to a common software framework.

The vacuum controls Section (TE-VSC-ICM) is in charge of the monitoring, maintenance and consolidation of the control systems of all accelerators and detectors in CERN; this represents 6 000 instruments distributed along 128 km of vacuum chambers, often of heterogeneous architectures and of diverse technical generations. In order to improve the efficiency of the services provided by ICM, to vacuum experts and to accelerator operators, a Quality Management Plan is being put into place. The first step was the standardization of the naming convention across different accelerators. The traceability of problems, requests, repairs, and other actions, has also been put into place (VTL). This was combined with the effort to identify each individual device by a coded label, and register it in a central database (MTF). Occurring in parallel, was the gathering of old documents and the centralization of information concerning architectures, procedures, equipment and settings (EDMS). To describe the topology of control components, the data structure is being defined, for later implementation (Layout-DB). Once complete, the quality and efficiency of ICM services can only improve, and appropriate performance indicators will be in place to display them.

During the first 3 years of LHC operation, the priority for the SCADA (Supervisory Control And Data Acquisition) of vacuum controls was to attend to user requests, and to improve its ergonomics and efficiency: access & presentation of information simplified and normalized; coherent functionalities & menus across all accelerators; automatic scripts instead of fastidious manual actions; enhanced tools for data analysis and for maintenance interventions. Several decades of cumulative developments, based on heterogeneous technologies and architectures, have been asking for a homogenization effort. The first LHC Long Shutdown (LS1) provides the opportunity to further standardize the vacuum controls systems [1], around Siemens-S7 PLCs (Programmable Logic Controllers) and PVSS SCADA. Meanwhile, exchanges with other Groups at CERN and outside Institutes have been promoted: to follow the global update policy for software libraries; to discuss philosophies and development details; and to accomplish common products. Furthermore, while preserving the current functionalities, a convergence towards the CERN UNICOS framework is under preparation.

The Large Hadron Collider makes extensive use of superconductors, in magnets for bending and focusing the particles, and in RF cavities for accelerating them, which are operated at 1.9 K and 4.5 K. The process automation for the cryogenic distribution around the accelerator circumference is based on 16 Programmable Logic Controllers, each running 250 control loops, 500 alarms and interlocks, and a phase sequencer. Spread along 27 km and under ionizing radiation, 15 000 cryogenic sensors and actuators are accessed through industrial field networks. We describe the main hardware and software components of the control system, their deployment and commissioning, together with the project organization, challenges faced, and solutions found.