Keeping a lid on high-volume food packaging

(See PLUS Automation at FoodManufacturing.Live, 15 October 2025, on stand 48)

A key feature of the C23PA series is the inclusion of the IO-Link serial connection protocol at no extra cost, providing the benefits of digital communication without requiring specialised cabling. So what does all of this mean for food packaging applications?

Modern food packaging plants are highly automated, relying on a multitude of sensors to keep things running smoothly. From conveying and wrapping to labelling and dispatch, each stage presents its own unique challenges. The primary goal for factory management is to achieve near-perfect uptime by pre-emptively addressing common issues that could lead to stoppages or faulty products reaching consumers.

The fundamental process remains the same: products are moved along a conveyor, sealed or wrapped, and then undergo secondary packaging and labelling. At every step, in-line checks are crucial to confirm the presence and correct orientation of items, as well as the proper application of packaging and labels. When multiple conveyors feed into a single line, the control system can even adjust their speeds to maintain a consistent flow.

The Contrinex C23PA series of miniature cubic photoelectric sensors is perfectly suited to meet these demands. These high-performance sensors are available in various types, including diffuse, background suppression, retro-reflex, through-beam, and transparent object in red light or uniquely UV-light.

Notably, the C23PA background-suppression sensors feature pinpoint LEDs, enabling the precise detection of small objects without resorting to laser technology.

In today's interconnected factories, plant-wide communication is a must. The C23PA series offers industry-standard PNP or NPN 3-wire or 4-wire outputs. Furthermore, the inclusion of IO-Link on all PNP devices allows for seamless digital communication without the need for special cabling, simplifying integration and offering remote diagnostics.

On fast-moving conveyor lines, the C23PA diffuse and background-suppression sensors excel at presence sensing and checking product orientation. These sensors can also be used to count items, calculating throughput rates that can exceed 1,000 items per minute.

Housed in a small, robust 20mm x 30mm x 10mm ABS casing, these sensors come with the choice of an integral M8 connector or a sealed 2-meter PVC cable. Their specialised optics provide excellent performance, even when detecting dark objects against light or reflective backgrounds, with sensing distances of up to 1500mm for diffuse and 300mm for background suppression models.

The C23PA family of sensors also benefits from having a range of complementary low-cost stainless-steel mounting and protection bracketry options.

For secondary packaging, C23PA retro-reflex sensors can monitor the flow of wrapped items, ensuring correct presentation and diverting any non-conforming products. The sensor's switching frequency can be adjusted via IO-Link to suit the specific needs of the application, from a standard 1.5 kHz to 500 Hz for finer tasks or 5 kHz for high-speed operations.

These sensors are also ideal for checking the dimensions of packed items, identifying any damaged or malformed packages and triggering a rejection sequence.

In the final packing area, C23PA through-beam sensors are the perfect choice for detecting and counting finished packages as they move to dispatch, offering sensing distances of up to 30 meters and an integral alignment aid for easy setup.

The power of IO-Link allows for remote communication with a plant-wide control system. In a flexible production environment where multiple product variants are run daily, this is a significant advantage. Sensor parameters can be reset remotely using predetermined values, minimising manual intervention during changeovers and keeping downtime to an absolute minimum.

With features like remote sensitivity adjustment, output reconfiguration, and the ability to set unique emitting sequences to prevent cross-talk between sensors, the C23 series offers unparalleled flexibility. The system also provides various event flags, including stability alarms, temperature and voltage warnings, and short-circuit detection.

The Contrinex C23PA Series offers a versatile, cost-effective, and highly reliable solution for the food and beverage industry. With a comprehensive international support network, customers have access to expert knowledge and relevant application experience, ensuring that best-in-class performance is paired with ultimate ease of use in even the most demanding environments.