Controls integration guide
Define how the bagger, dosing system, product feed, coder, inspection, reject equipment and downstream machinery exchange states before software and wiring are finalised.
Direct answer
For every connection, record the source, destination, normal state, trigger, required response, fault state, reset condition, timing and responsible supplier. Apply the schedule to normal running, starvation, blocking, product or film low, coder and inspection faults, rejection, guard or emergency stops, network loss and power restoration. The result becomes a design, FAT and SAT reference.
Boundary
Start with one controlled line layout showing product feed, filler or weigher, VFFS machine, coder, inspection, reject, discharge conveyor, accumulation and secondary packing. Number each mechanical, electrical, product, utility, control and data boundary. State what is supplied, connected, tested and approved by each party.
States
A signal called “ready” is incomplete unless its meaning is agreed. Specify whether ready means powered, guards healthy, recipe loaded, product available, film available and able to accept a start. Define starved, blocked, held, faulted and stopped conditions separately so an upstream or downstream event produces a predictable response.
Recovery
When a coder, camera, checkweigher or reject system changes state, packs may already exist between the detection point and the physical response. Document the tracking method, lane identity where relevant, pack count and restart rule. Recovery must identify which packs are accepted, rejected or placed on hold.
Interface matrix
The exact architecture remains project-specific; this matrix identifies the decisions that should not be left until site installation.
| Condition | Definition required | Acceptance evidence |
|---|---|---|
| Filler or weigher not ready | Whether the bagger waits, inhibits film movement, completes a pack or enters a controlled stop. | Challenge the ready signal during start-up, stable running and restart; confirm no empty or uncontrolled pack is released. |
| Product low or refill demand | Demand, low-level, high-level and fault logic between bulk feed, hopper and dosing system. | Run through replenishment and interrupted refill; confirm product condition and dose remain within the agreed acceptance rule. |
| Downstream blocked | Available accumulation, run-out quantity, stopping sequence and recovery ownership. | Block the discharge at agreed rates; trace every pack and prove the restart sequence. |
| Coder not ready or code fault | Production inhibit, controlled stop, hold or reject rule and message/recipe ownership. | Remove ready, create a print fault and verify affected-pack identification and disposition. |
| Inspection failure | Detection rule, pack tracking, reject command, reject confirmation and unavailable-reject response. | Use controlled challenge samples and prove the failed pack reaches the secured reject path. |
| Guard or emergency stop | Safety function, controlled energy response and the non-safety control state presented to the line. | Validation by competent persons plus a documented pack-recovery procedure after reset. |
| Network or data loss | Required local operation, alarm, data buffering, read/write permissions and safe/fault state. | Interrupt communications and verify machine behaviour, data integrity and controlled reconnection. |
| Power restoration | Recipe, counters, machine state, heaters, product/feed state and permission to restart. | Restore power from defined conditions and verify that no automatic movement or pack release occurs outside the approved sequence. |
Local controls
The human-machine interface may contain recipes, alarms, manual functions, counters and maintenance screens, while line interaction occurs through discrete I/O, an industrial network or a combination. Specify user levels, recipe ownership, alarm text, retained data and which commands can cross the machine boundary. Read-only monitoring and remote write access require different controls.
Optional standardisation
PackML can provide consistent modes, states and data tags across packaging equipment. It does not remove the need to define the actual product, quality and recovery behaviour. Record the adopted model, version, required states, data tags and HMI conventions in the project specification. OMAC publishes packaging-workgroup guidance on PackML user interfaces and state presentation.
FAT and SAT
Buyer questions
Provide a line layout, equipment list, product-flow direction, target accepted output, operating states, existing control platforms, network constraints, coder and inspection scope, reject requirements and the intended response to starvation, blocking and faults. The supplier can then define the interface boundary instead of assuming how neighbouring equipment will behave.
The exact interface is project-specific, but it commonly needs unambiguous ready, demand, discharge-permitted, dose-complete, low-product and fault states. Each signal should have a named source, destination, normal condition, trigger, response and reset rule. Product movement must remain coordinated through stop, restart and recipe change.
The response depends on buffer capacity, product and pack behaviour, pack tracking and the safe recovery sequence. The line may stop immediately, run out a controlled number of packs or use accumulation. The chosen behaviour should prevent untracked packs, crushed bags, lost rejects and an uncontrolled restart.
PackML is not automatically mandatory. It can provide a consistent machine-state and data model when the customer, controls platform and connected equipment adopt it. A project may instead use discrete handshakes or another agreed interface. The requirement, version, states, tags and acceptance tests should be written into the controls scope.
Define whether each fault inhibits production, creates a controlled stop, diverts affected packs or places product on hold. The line must know which pack was printed or inspected, how it is tracked to rejection, whether rejection was confirmed and what happens when the reject container or reject mechanism is unavailable.
Test normal running and every agreed abnormal state: product low, film low, filler fault, coder not ready, failed inspection, reject not confirmed, downstream blocked, emergency stop, guard opening, network loss, power restoration and recipe change. Record the expected response, actual response, recovery steps and disposition of packs remaining in the line.
Controls review