Editing Distributed control system (section)

{{Short description|Computerized control systems with distributed decision-making}}
{{Use British English|date=February 2018}}
{{Manufacturing}}
A '''distributed control system''' ('''DCS''') is a computerized [[control system]] for a process or plant usually with many [[control loop]]s, in which autonomous controllers are distributed throughout the system, but there is no central operator supervisory control. This is in contrast to systems that use centralized controllers; either discrete controllers located at a central control room or within a central computer. The DCS concept increases reliability and reduces installation costs by localizing control functions near the process plant, with remote monitoring and supervision.

Distributed control systems first emerged in large, high value, safety critical process industries, and were attractive because the DCS manufacturer would supply both the local control level and central supervisory equipment as an integrated package, thus reducing design integration risk. Today the functionality of [[SCADA|Supervisory control and data acquisition (SCADA)]] and DCS systems are very similar, but DCS tends to be used on large continuous process plants where high reliability and security is important, and the control room is not necessarily geographically remote. Many machine control systems exhibit similar properties as plant and process control systems do.<ref>{{Cite book |last=Eloranta |first=Veli-Pekka |title=Designing distributed control systems: a pattern language approach |last2=Koskinen |first2=Johannes |last3=Leppänen |first3=Marko |last4=Reijonen |first4=Ville |date=2014 |publisher=Wiley |isbn=978-1-118-69415-2 |series=Wiley series in software design patterns |location=Chichester}}</ref>