Glossary · Engineering, integration and validation
Control narrative
Also known as: Control philosophy, Functional description
German: Steuerungsbeschreibung
In industrial automation, a control narrative is a prose description of how a plant section, unit or machine is to be controlled, including operating modes, sequences, control loops, interlocks, alarms and operator actions. It links process design and control software.
- Validation
- Process industry
- Technical documentation
In one sentence
A control narrative describes in prose how a unit or machine is controlled: modes, sequences, loops, interlocks, alarms and operator actions.
Example
The control narrative for the CIP skid describes the rinse, caustic and acid steps, their temperature setpoints and what happens if the return flow is too low.
How it applies
- Engineering: Process engineers and control engineers write the narrative together; programmers implement the software from it, and reviewers check the code against it.
- Commissioning: Test cases for the Factory acceptance test (FAT) and Site acceptance test (SAT) are derived from the narrative, sequence step by sequence step.
- Operation: Operators and trainers use it to understand why the system reacts the way it does, especially during abnormal situations.
- Documentation: The documentation team can reuse the narrative as a source for operating instructions, but must rewrite it for the user's task and verify it against the as-built software, because narratives often describe design intent rather than the final state.
Control narrative vs. cause-and-effect matrix
The narrative describes behavior in text, which suits sequences and operator interaction. The Cause-and-effect matrix captures discrete interlock and trip logic in a table. Keep both consistent and cross-reference them by tag number.