A distributed control system (DCS) is a computerized control system for a process or plant, in which autonomous controllers are distributed throughout the system, but there is a control control of the central operator. This contrasts with non-distributed control systems using centralized controllers; whether discrete controllers located in a central control room or within a central computer. The DCS concept increases reliability and reduces installation costs by locating control functions near the process plant, but allows you to monitor and monitor the process remotely.
Distributed control systems first emerged in large process industries with high safety critical value and were attractive because the DCS manufacturer would supply both the local control level and the central monitoring equipment as an integrated package, thereby reducing the risk of integration of the design. Today the functionality of SCADA and DCS systems is very similar, but DCS tends to be used in large continuous process plants where high reliability and safety is important, and the control room is not geographically remote.
Increasingly, and ironically, DCS are being centralized at the plant level, with the ability to log on to the remote computer. This allows the operator to control both enterprise (macro) level and (micro) equipment level inside and outside the plant as physical location due to interconnection mainly because wireless and remote access has been reduced.
As wireless protocols are developed and refined, DCS increasingly includes wireless communication. DCS controllers are now often equipped with integrated servers and provide web access on the go. Whether DCS will conduct IIOT or borrow key elements from the remains to be established.
Many vendors offer the option of a mobile HMI, ready for Android and iOS. With these interfaces, the threat of security breaches and possible damage to the plant and process are now very real.