DCS
What are Distributed Control Systems?
A Distributed Control System (DCS) is an automation technology that uses independent controllers distributed throughout a plant. These controllers operate autonomously, without the need for central supervisory control.
They communicate with each other across the plant using peer-to-peer communication via a redundant internal communications network.
The physical DCS controllers are typically housed in panels, often located in HVAC-cooled rooms at various points around the facility, near the process equipment and instrumentation.
The deployment of DCS controllers within enclosures across a facility is also becoming increasingly common. This is due to advancements in DCS technology, which have led to reduced footprint and programmable I/O capabilities.
DCS products typically include a comprehensive suite of software applications that serve purposes beyond basic plant control, including alarm management, instrument loop tuning, and process control optimization.
Some examples of market leading DCS platforms are:
- Honeywell Experion/TDC
- Emerson DeltaV DCS/SIS
- Yokogawa CENTUM DCS/ProSafe
- ABB 800xA
What are the Key Skills Needed to Work with Distributed Control Systems?
DCS Platforms:
- Setting up the DCS database and historians.
- Configuring interfaces to various external automation systems and equipment.
- Configuring workstation clients and managing user access.
- Developing intuitive HMI in line with P&IDs and other process inputs.
DCS Network Design:
Modern DCS are characterized by large, complex multi-topological DCS networks. DCS engineers must be able to design DCS networks based on the spatial arrangement of plant automation equipment and instrumentation, considering all environmental constraints, as well as end-user requirements for network manageability, availability, and latency.
Command Line Scripting:
Bash and command line scripting are heavily used during DCS integration for setting up scheduled processes and automating tasks between servers. They are also frequently used as first-line tools for troubleshooting network adapters and communications issues.
Databases:
Modern DCS integration involves working with a lot of databases; these are used for storing the configuration, process data, alarms, and events, etc. DCS engineers must be able to design, configure, and manage relational databases commonly used in DCS, such as SQL Server, Oracle, MySQL, and OSIsoft.
Virtualization:
Modern DCS platforms use virtualization for their servers and HMIs; therefore, it's important to have skills for using hypervisors and managing virtualized architectures. DCS engineers should be able to work with hypervisors used by market-leading DCS providers such as Microsoft Hyper-V, VMWare vSphere, and Dell VRTX.
Windows Server:
Most DCS platforms run on Windows server environments. Therefore, it’s essential to know how to configure and manage users and group policies in the Windows Active Directory environment.
Programming Skills:
Java, HTML, JavaScript, VBA are used extensively for developing highly customized operator interfaces (HMI). HTML and JavaScript are used by many of the modern DCS systems that use web-based operator clients. Many older and legacy DCS systems use VBA for HMI development, such as DeltaV (version before V14).