Direct answer
Define the operational state model, commands, modes, tags, ownership and exception behaviour before choosing a protocol. PackML can provide consistent machine states and interfaces; OPC UA can expose structured machine information securely to line and supervisory systems.
Why this matters
A network connection alone does not create useful integration. Data meaning, timing, quality, authority and fail-safe behaviour must be agreed between machine suppliers and the site.
Decision table
| Interface layer | Define | Example |
|---|---|---|
| Machine state | Consistent modes and states | Execute, stopped, held or aborted |
| Line handshake | Ready, blocked, starved and fault ownership | Controlled product flow |
| Production data | Counts, speed, rejects and reason codes | OEE and diagnosis |
| Recipes | Parameters, version and access | Repeatable changeover |
| Security | Accounts, certificates, ports and update ownership | Managed OT connection |
Information to collect
- Create a tag and state responsibility matrix.
- Agree which controller owns each command.
- Define timestamp and count boundaries.
- Name communication-loss behaviour.
- Separate production data from safety functions.
- Plan certificates, accounts, backups and change control.
Practical method
- 1
Use one common machine-state convention.
- 2
Map data to business questions before collecting it.
- 3
Test normal and abnormal handshakes.
- 4
Validate time synchronisation and counter reconciliation.
- 5
Document the final interface after commissioning.
Common mistakes to avoid
- Assuming identical tag names mean identical meaning.
- Letting supervisory systems write uncontrolled recipe values.
- Using network status as a safety function.
- Collecting every tag without purpose.
- Commissioning interfaces without fault scenarios.
Questions people also ask
What is PackML?
PackML is a common operational model intended to make machine states and interfaces more consistent across production equipment.
What is OPC UA used for?
It provides a structured framework for exposing and exchanging machine information.
Do all machines need the same PLC?
No, but interfaces, data meaning, security and fault behaviour must be compatible and documented.
Can OPC UA calculate OEE?
It can supply structured data; OEE still depends on agreed boundaries, definitions and business logic.
Official and primary sources
These references support the regulated, standards-led or security points in this guide. Check the current source before making a project decision.
Continue from the requirement to the equipment
Use the specialist route that matches the product, pack and process. Final suitability requires representative samples, output targets and site information.