This chapter contains an overview of the various systems that provides utilities or
support the main process.
Control and Safety Systems
A process control system is used to monitor data and control equipment on the plant.
Very small installations may use hydraulic or pneumatic control systems, but larger
plants with up to 30.000 signals to and from the process require a dedicated
distributed control system. The purpose of this system is to read values from a large
number of sensors, run programs to monitor the process and control valves switches
etc. to control the process. At the same time values, alarms, reports and other
information are presented to the operator and command inputs accepted.
Process control systems consist of the following components: