Application guide
What is a retrofit vision inspection system?
A retrofit vision inspection system adds automated camera inspection to an existing production or packaging line. The project must fit around installed machinery while creating repeatable imaging, safe access, a reliable controls interface and enough distance to associate every result with the correct product response.
A retrofit can cover one focused check—such as a date code—or combine label, closure, seal, fill, pack identity and visible defect checks within a multi-camera cell. Site measurements and sample trials determine which arrangement is practical.
Inline retrofit, standalone machine or mounted module?
Inline retrofit
Cameras, lights and controls can be arranged around an existing conveyor when it already presents products consistently and provides enough access. This can reduce added footprint, but the existing guides, guarding and reject distance may constrain the camera geometry.
Standalone inspection machine
A self-contained conveyor module provides clearer ownership of presentation, enclosure, electrical controls and rejection. It needs more line length but can reduce dependence on the condition of an older conveyor.
Machine-mounted inspection module
The best view may be inside or immediately after a filler, capper, sealer, labeller or cartoner. This option needs close mechanical, safety and controls coordination with the original equipment.
What the retrofit site survey checks
- Conveyor width, height, available line length and maintenance access
- Product pitch, speed, accumulation, vibration, guides and transfers
- Where each required feature is visible before another process hides it
- Ambient light, washdown, dust, temperature and cleaning constraints
- Guarding, operator access and safe recovery after a fault
- Power, air, network, PLC, encoder and trigger interfaces
- Distance from image capture to failed-product containment
Product handling often determines inspection reliability
A camera cannot compensate for a feature that repeatedly leaves the field of view or focal range. Side belts, guide changes, timing screws, transfers, sensors or a short dedicated conveyor may be needed to control position and spacing. Physical format changes and software recipes should be designed together so changeover settings remain repeatable.
Controls, recipes and fault behaviour
The vision system may exchange triggers, product selection, ready and fault states, results, alarms and line-stop requests with the existing PLC. The interface boundary and ownership of recipe selection are agreed early. The fault strategy should cover blocked sensors, loss of air, communication failure, full reject bins and the wrong product recipe.
Track each result to confirmed rejection
Inspection and rejection may be separated by several product pitches. Encoder or timed tracking associates the camera decision with the correct pack as speed changes. Reject hardware is selected for product weight, stability, spacing and failure mode, with confirmation and secure collection added where required.
Plan installation and acceptance before the shutdown
Off-line build, simulation and sample trials can reduce production downtime. The project should still define the site tie-ins, planned shutdown, challenge samples, line-speed test, reject confirmation, alarm tests and recovery sequence. FAT and SAT responsibilities should be stated in the quotation.
Inputs that shorten the route to a proposal
- Marked-up layout, conveyor measurements and recent line video
- Product range, dimensions, materials and changeover method
- Maximum speed, minimum pitch and accumulation behaviour
- Good samples and representative failed or borderline packs
- Existing PLC, network, electrical and safety standards
- Required reject, alarm, stop, record and acceptance strategy
Plan the full retrofit scope
Use the vision-system guide, cost guide, specification checklist and automatic reject guide.