Glossary · Control theory and process control
Process control system architecture
Also known as: DCS architecture, PCS architecture
German: Prozessleitsystem (PLS)
In process automation, the process control system architecture is the structure of a process control system: operator and engineering stations, servers, controllers, I/O and the networks between them, arranged in levels and often with redundancy.
- Control theory
- Process industry
In one sentence
Process control system architecture describes the stations, servers, controllers, I/O and networks of a process control system and how they connect.
Example
The architecture drawing of the new plant shows redundant servers, four operator stations, one engineering station, twelve redundant controllers with remote I/O and a separate plant network zone.
How it applies
- Engineering: Architecture decisions cover controller allocation, Redundancy of controllers, servers and networks, I/O placement (central, remote, marshalling) and the interfaces to MES and business systems. Network segmentation follows the Security zone and Conduit model of IEC 62443.
- Operation: The architecture determines what continues to work when a component fails. Operators need to know which views or functions degrade.
- Documentation: Keep an up-to-date architecture drawing with device names, network addresses (in controlled documents), software versions and redundancy concept. It is the starting point for maintenance, cybersecurity assessments and change impact analysis.
Architecture vs. system
The Process control system is the whole installed system with its functions. The architecture is its structural description; two plants with the same product can have very different architectures.