Control that is dedicated to establishing and maintaining a specific state of equipment or process condition.
NOTE - Basic control may include regulatory control, interlocking, monitoring, exception handling, and discrete or sequential control.
Basic control comprises the control dedicated to establishing and maintaining a specific state of equipment and process. Basic control
* includes regulatory control, interlocking, monitoring, exception handling, and repetitive discrete or sequential control;
* may respond to process conditions that could influence the control outputs or trigger corrective actions;
* may be activated, deactivated, or modified by operator commands or by procedural or coordination control.
Basic control in a batch environment is in principle no different from the control of continuous processes. However, in the batch environment, there may be higher requirements on the ability for basic control to receive commands and to modify its behavior based on these commands.
User Requirements specifications for basic control are covered by the P&ID however often the level of detail on a P&ID is insufficient and additional loop diagrams, or function block diagrams are required See also control module and equipment module