42 n MAINTENANCE, SERVICE AND REPAIRS September 2026 www.drivesncontrols.com Dairy keeps pallets moving after muting system goes obsolete The Austrian company NÖM (Niederösterreichische Milch) is one of Europe's most modern dairy producers. At its facility in Baden, it processes and packages around one million litres of milk every day, before distributing the products to domestic and export markets. Maintaining continuous operation is critical. “Over a year, we take around 420 million kilograms of raw milk and turn it into yoghurt, curd (quark), butter, cocoa, kefir, protein drinks and much more”, explains Christina Keil from NÖM's corporate communications department. At least one million litres of raw milk is delivered every day, from a total of 2,500 family-run milking businesses. This meant that when an obsolete muting relay used in the site's palletising operation needed to be replaced, unplanned downtime became a significant concern. NÖM's history dates back to 1898, when Frank von Pirko founded the company. From its origins as a regional dairy, it has developed into an internationally successful manufacturer, with exports now accounting for around 45% of its production. The company’s fresh food warehouse is staffed around the clock to ensure that NÖM's products are ready to ship as quickly as possible. Extended plant downtimes need to be avoided at all costs, especially as this is the company’s only production site. When a muting relay used on around 30 palletiser entry and exit points, was discontinued, with no successor being offered, NÖM’s head of control technology, Michael Hronek, faced a challenge: finding a replacement that could be integrated without affecting operations. “The problem was that the existing application was not so easy to replicate because, in our case, a higher-level controller is involved in the muting,” he explains. “And it shouldn’t be affected by any of the conversions that had become necessary.” As a result, it was necessary to replicate the functions of the existing relay and its interaction with the light curtains from the same supplier. NÖM's chose a small configurable controller – a Pilz PNOZmulti 2 – to take over management of the muting function for the infeed and outfeed of goods, ensuring controlled, temporary suspension of safety functions during pallet transfers. Any changes that affected the controller were synchronised with the CIP (cleaning-in-place) that was scheduled every few days. To avoid additional downtime, Pilz also installed its PSS 4000 automation system for multiple stations in one weekend. As part of the project, two of NÖM's three palletising systems were upgraded and the previous relays and safety light curtains were replaced. The need for flexibility The task was to replace the existing relays and light curtains while maintaining the functions of the optoelectronic safeguarding system. “The ability to work with a wide range of dual-channel safety devices was a major advantage for us,” Hronek reports. “At a time when many components are subject to long lead times and supply constraints, flexibility is extremely important.” The new system met NÖM's key requirements: reliability; a high level of safety; and the ability to adapt easily to changing requirements; while leaving higher-level plant controls unaffected. All of this was only achieved after intensive study of the manual for the monitoring system with an integrated muting controller that was being replaced, particularly as it was not only a case of replicating a specific communication or switching sequence, but of also maintaining a specified time cycle. “If the plant controller signals the arrival of a pallet, the PNOZmulti or PSS 4000 now performs the role of the previous muting relay, removes two control outputs, has the operation confirmed by our higher-level standard CPU, and only then enables the goods to be transported,” Hronek explains. “In the meantime, the functionality of the connected light barriers is also monitored cyclically, and the positioning of the pallet is checked. "Only a few of the original devices remain in operation, but if additional replacements become necessary, we now have a plugand-play solution available,” Hronek adds. “That's a significant advantage for us.” n An Austrian dairy faced a significant problem when a muting relay used on around 30 palletiser entry and exit points, was discontinued, with no successor being available. By turning to a configurable safety controller, the dairy was able to replicate the functions of the obsolete system with minimal disruption to its operations. The dairy’s previous relays and safety light curtains have been replaced as part of the project in which two of its three palletising systems were upgraded
RkJQdWJsaXNoZXIy MjQ0NzM=