The OPC UA Compressed Air Systems (CAS) Companion Specification includes a description of a system and a basic description of its components regarding a Compressed Air System. Main scope of this specification is the communication between the Main Control Systemand the higher-level manufacturing system(s). More specific, it is the transport of condition data of a CAS vertically into higher level manufacturing systems (MES; etc.) for information and monitoring purposes and to set basic parameters regarding the target values of the respective CAS. The description of the CAS and its components is focused on selected use cases, e. g. device identification, configuration, maintenance management, energy management, and operation.

This Companion Specification is not intended to provide viable representations for components such as compressors or dryers outside the context of a compressed air system. It is not intended to use parts of this Companion Specification outside the context of a compressed air system. Particularly, it is not intended to use the components in the context of machine-to-machine communication.

Note: The focus lies on the system which the MCS represents. The MCS communicates with other machines outside of this system. It matches the demand of several users with the compressed air generation by controlling the components especially the compressors of that compressed air system. Therefore, this Companion Specification cannot be directly compared with a Companion Specification for direct machine to machine communication where the component is directly integrated in another machine or process like the Companion Specification for pumps, machine tools, etc.