Integration of new cryogenic plants into an existing control system: a scalable and standardized approach

The High-Luminosity upgrade of the Large Hadron Collider (HL-LHC) requires integrating new cryogenic plants while ensuring uninterrupted operation of the existing infrastructure. This paper presents a scalable and standardized approach to upgrading the control system, ensuring flexibility, interoperability, and long-term maintainability. The approach utilizes commercial off-the-shelf (COTS) components, including PLCs and standard programming languages compliant with IEC-1131, to enable modular deployment and minimize development complexity. Additionally, the use of a control framework (UNICOS) streamlines implementation, enhances system coherence, and ensures efficient interaction between new and legacy subsystems. We provide an overview of the control system architecture, highlighting design decisions that enhance scalability and adaptability. Challenges such as maintaining a seamless integration with the operational constraints, reliability assurance, and automation consistency were addressed through structured methodologies. This work serves as a reference for large-scale cryogenic system upgrades, demonstrating how industry standards and COTS solutions facilitate integration while ensuring long-term sustainability.