MOVIGEAR is ideal for this application due to its speed range
Leading drive and automation specialist SEW-EURODRIVE (Pty) Ltd. has supplied 64 MOVIGEAR® geared servo motors from its Cape Town branch to a major local Original Equipment Manufacturer (OEM) based in Paarl, H.G. Molenaar that, in turn, designed, manufactured, and supplied a weighing conveyor system to a German-based company that is a leader in the frozen fish and vegetable packing sector.
The system comprises a central conveyor fed by eight smaller weighing conveyors, each containing the various frozen-food products to be mixed according to specification. Each conveyor has a separate loadcell to determine the exact weight of the component products. Meanwhile, the overall speed, precision, and quality of the entire process is controlled by a master PLC.
Paul Strzalkowski from SEW-EURODRIVE (Pty) Ltd. commenced the design of the project with engineers from H.G.Molenaar in December 2017, clinched the initial order in March 2018, and completed the actual project in February this year.
The MOVIGEAR® solution was ideal for this application due to its 200:1 speed range, together with the fact that these units are designed specifically for the strict hygiene requirements of the food-and-beverage industry. In this regard, the units have no sharp edges or corners where bacteria can accumulate, in addition to featuring a special H200 protective coating. This was added to the surface of the MOVIGEAR® to protect against all types of chemical cleaning agents used when cleaning of the plant.
“The gearbox and motor are a single sealed unit, together with all of the electronic controls,” explains Strzalkowski, who heads up Mechatronic Sales at the Cape Town branch. This equates into a significant saving in terms of the panel size required.
“Panel space was a definite consideration with this project, which meant there was no space for centralized, bulky speed controllers. Hence the compact modularity of the MOVIGEAR® units was ideal,” Strzalkowski elaborates.
Another feature is on board input/output controls that interact directly with the MOVIGEAR® electronics, meaning no additional wiring to the master PLC. Thus, all control is via the SBUS protocol directly from the master PLC daisy-chained to the drives themselves.
In addition, the turnkey solution provided by SEW-EURODRIVE (Pty) Ltd. had to contend with an extreme temperature range from -25°C to 25°C. A special oil for food-and-beverage applications was also required to protect against any harm caused in the unlikely event of any leaks developing.
While the food-and-beverage MOVIGEAR® unit is a standard product, the economies-of-scale dictated by this project meant that the major order was sourced from Germany itself. Strzalkowski highlights that the Cape Town branch is fully-equipped to assemble these units locally, and indeed supplies them to a range of industries and applications in Southern African.
Commenting on the feedback received to date, Strzalkowski comments that the client is particularly happy from a commissioning point of view, due to the considerable saving on wiring installation, cost, and time. “The big surprise for the end user has been that the energy consumed while all the drives are running is at least 50% lower than anticipated.”
Strzalkowski concludes: “The beauty of MOVIGEAR® is everything is prewired. Each unit is daisy-chained, which results in the major reduction in cabling achieved. This was a major flagship project for the flexibility and cost-saving benefits of the MOVIGEAR® solution.”