Safety light curtains for F&B applications with IP69K Washdown-rating

Perhaps the most memorable product name within the ReeR catalogue, the WTF Safety Light Curtains indicate their Water-Tight-Food performance, not ‘what the flip’, if that’s what you thought.

In the fast-paced demanding world of food and beverage manufacturing, the twin demands of operator safety and rigorous hygiene standards often present a significant engineering challenge. Equipment must not only protect personnel from high-speed machinery but also withstand the aggressive daily cleaning regimes essential for food safety.

To meet these requirements, ReeR Safety offers variants of it’s EOS range of safety light curtains with watertight enclosures, specifically engineered to provide robust protection for light curtains in the harshest industrial environments.

Meeting the IP69K challenge

For automation engineers, the IP69K rating is the gold standard for ingress protection. ReeR’s EOS WTF (Water-Tight- Food) and WTHF (Heated) enclosures are designed to withstand high-pressure water jets of up to 100 bar at temperatures reaching +80°C.

Constructed with a slimline cylindrical profile of just 56mm in diameter, these enclosures use PMMA (polymethyl methacrylate) transparent housings and POM-C (acetal resin) sealing caps. These materials are chemically inert and non-toxic, ensuring they meet Ecolab standards and are fully compatible with the detergents and disinfectants commonly used in the industry.

Managing condensation and cold storage

Temperature fluctuations in food processing, particularly in meat and dairy, frequently lead to condensation, which can interfere with optical safety barriers. To combat this, the EOS enclosures feature an integrated GORE valve to equalise pressure and prevent moisture build-up.

For applications in sub-zero environments, such as industrial freezers or refrigerated warehouses, ReeR offers the WTHF (Heated) version. These units feature a thermostatically controlled heating system, allowing the light curtains to operate reliably in temperatures as low as -25°C.

Application insight: High-speed packaging

The practical benefits of this technology are evidenced in its adoption by major food packaging machinery manufacturers. In one recent application involving a high-speed line between a slicer and a thermoforming machine, the manufacturer required a safety solution that didn't impede visibility or access.

While traditional physical guarding is often used to prevent unintentional stops, it can restrict a technician’s ability to clear jams or perform routine maintenance. By implementing EOS4 WTFs light curtains, the manufacturer achieved a high level of safety without compromising throughput.

These machines which dose, overlap, and load products like cold cuts and cheeses require frequent washdowns. 

The use of stainless steel and Ecolab-approved enclosures ensures that the safety components are as durable as the machine frame itself, preventing premature failure due to corrosion or water ingress.

Key technical specifications:

• Protection Grade: IP69K (Resistant to 80–100 bar jets at 80°C).
• Material Integrity: PMMA and POM-C construction; inert and food-safe.
• Operating Range: Standard models for ambient use; heated (WTHF) models for environments down to -25°C.
• Connectivity: Supplied with 10-metre pre-wired cables and integrated cable glands for simplified installation.
• Resolutions: Available in 14mm (Finger) and 30mm (Hand) detection, alongside multi-beam versions for access control.

As manufacturers continue to automate high-speed processing lines, the need for components that can survive the washdown and freeze cycle is paramount. By combining optical precision with heavy-duty environmental protection, ReeR Safety is helping the industry bridge the gap between maximum productivity and uncompromising safety standards.

www.plusautomation.co.uk