Distributed Control System - Definition and Overview

A distributed control system (DCS) is part of a manufacturing system. Distributed control systems (DCS) are used in industrial and civil engineering applications to monitor and control distributed equipment with remote human intervention. It is generally, since the 1990s, digital, and normally consists of field instruments, connected via wiring to computer buses or electrical buses to multiplexer/demultiplexers and A/D's or analog to digital and finally the Human-Machine Interface (HMI) or control consoles. DCS is a very broad umbrella that describes solutions across a large variety of industries, including:

• Electrical power distribution grids and generation plants
• Environmental control systems
• Traffic signals
• Water management systems
• Refining and chemical plants

The broad architecture of a DCS solution involves either a direct connection to physical equipment such as switches, pumps and valves or connection via a secondary system such as a SCADA system. A DCS solution does not require operator intervention for its normal operation, but with the line between SCADA and DCS merging systems claiming to offer DCS may actually permit operator interaction via a SCADA system. In the 1990s pneumatic control systems began to be replaced by DCS's.

See also:

• SCADA