Glossary · System coordination, integration and orchestration
Startup sequence
Also known as: Startup procedure, Start-up sequence
German: Anfahrsequenz
In industrial automation, a startup sequence is the defined series of steps by which a machine, unit or plant is brought from a shut-down state into normal operation, for example by checking preconditions, homing axes, bringing utilities online and starting units in a set order.
- System integration
- Process industry
In one sentence
A startup sequence brings a machine, unit or plant step by step from a shut-down state into normal operation.
Example
The startup sequence of a compressor station checks oil pressure, starts the lubrication pump, opens the suction valve and only then starts the compressor motor.
How it applies
- Engineering: Define preconditions and the order of starting subsystems; in lines, downstream machines are usually started first so material can flow out. Each step needs feedback before the next starts.
- Commissioning: Test startup from cold and warm states, and aborted startups.
- Safety: Start commands must be deliberate. The machinery safety concept must rule out Unexpected startup, and in some cases warning signals before startup are required by the risk assessment.
- Documentation: Describe preconditions, checks and the startup procedure in the operating instructions. Link to any Pre-startup inspection required after maintenance or modification.
Startup sequence vs. restart sequence
A startup sequence begins from a known, shut-down state. A Restart sequence begins after an interruption and must first restore a consistent state, for example by clearing partial products.