When sourcing a filling and packaging line, much of the attention naturally goes to equipment specifications, throughput, performance and price. But one critical detail can be overlooked until commissioning: how equipment supplied by different OEMs will communicate with each other at the automation level.
On modern filling and packaging lines, this matters because the process equipment, primary filling machine and secondary packaging equipment often come from different suppliers. Each machine may perform perfectly on its own, but the complete line will only operate as one system if the automation interfaces between them have been properly defined.
When those interfaces are not agreed early enough, what appears to be a small technical detail can quickly become a source of project delays, additional engineering work and unplanned cost.
The Multi-OEM Integration Challenge
It is relatively uncommon for every part of a complete production line to come from a single OEM. A project may combine process equipment from one supplier, a filling machine from another, and downstream packaging equipment from several others.
All of those systems still need to exchange information reliably.
Think of it as the OEM handshake: one machine needs to know the status of another before the correct sequence can continue.
A simple example is a CIP (Clean-in-Place) plant supplied by one OEM that needs to communicate with a filling machine supplied by another OEM. For the filler to be cleaned correctly, the two systems must exchange the required signals reliably and in the correct sequence, every cycle, without depending on manual intervention.
Why the Problem Becomes Expensive Later
The difficulty is not simply that different machines need to communicate. The communication method, signal definitions, ownership and responsibilities also need to match.
If these requirements are unclear when equipment is purchased, the problem may not become obvious until installation or commissioning, when both systems are physically on site and expected to work together.
At that point, resolving the mismatch can require PLC software changes, additional wiring or hardware, engineering changes, scope clarification and commercial negotiation between OEMs that have already priced and delivered their equipment.
The technical problem is still solvable, but the timing makes it slower and more expensive.
What to Confirm Before You Sign Off an OEM Package
The automation interface should be reviewed in detail during the sourcing and design stage. Do not assume that two machines will simply communicate because both suppliers know they are part of the same line.
- Identify every signal that needs to be exchanged.
Map each point where one OEM’s equipment needs to send information to or receive information from another system. Typical signals may include:
- Start / stop
- Ready / not ready
- Running status
- Fault or alarm status
- Permissives and interlocks
- Cleaning-in-progress or CIP status
- Cycle or sequence confirmation
For each signal, confirm which system sends it, which system receives it and which OEM is responsible for implementing and testing it.
- Agree how the signals will be exchanged.
The signal itself is only half of the interface. Both sides also need to agree on how that information will be transmitted.
Depending on the equipment and controls architecture, signal exchange may use an industrial fieldbus or network, TCP/IP-based communication, or hard-wired I/O. The important point is that both OEMs agree on the interface method and implement compatible requirements.
If one OEM designs its interface around network communication while the other expects hard-wired signals, the mismatch may remain hidden until commissioning.
- Define ownership and responsibility.
A clear interface specification should state who provides the communication hardware, who writes or modifies the PLC logic, who supplies the signal list, and who is responsible for testing each side of the interface.
Without clear ownership, an integration problem can easily turn into a discussion about whose scope it belongs to.
- Review the sequence, not only the individual signals.
A list of signals does not automatically prove that two systems will operate correctly together. The expected operating sequence should also be understood: what happens first, what conditions must be satisfied before the next step, and how each system responds to faults, stops or recovery conditions.
Why This Belongs in Sourcing and Design – Not Commissioning
Commissioning should be the stage where an agreed interface is tested and proven, not the first time the interface is properly defined.
Catching an automation compatibility issue before purchase orders are finalised gives the project team the opportunity to include the required hardware, software, engineering effort and responsibilities within the OEM scope.
Finding the same issue after equipment arrives on site can mean negotiating changes while the commissioning schedule is already running.
That is why automation-interface review should form part of technical due diligence when evaluating equipment from multiple OEMs.
A Small Interface Detail Can Affect the Whole Packaging Line
A production line is only as integrated as the machines that make it up. Individually capable equipment does not guarantee a well-integrated line.
Before approving a multi-OEM filling or packaging project, make sure the signal exchange, communication method, sequence and responsibilities between suppliers are clearly understood.
Ask the automation-interface questions before you sign – not after the equipment arrives on site.
At Zunachi Ltd, we support filling and packaging projects with installation, commissioning, PLC and automation troubleshooting, and production optimisation. This includes reviewing OEM automation interfaces during the sourcing and design stage so that integration issues can be identified before they become commissioning problems.