PECM Issue 17 2015 | Page 8

DIGITAL DMS BASED LOAD CELLS OPEN THE DOOR TO NEW MARKETS With the manufacturing industry demanding technology that is both accurate and affordable, Bernd Knöll, Product Manager, HBM GmbH, looks at how new digital DMS based load cells can open the door of opportunity to machine manufacturers. A s continuous growth, high competitive pressure and large production quantities in the manufacturing industry look set to continue, particularly within expanding markets such as China, India and East Asia, the entire processing chain, including manufacturers of packaging machines and checkweighers, is placed under greater performance pressure than ever before. Confronted with the demand for ever increasing precision and higher speeds for packaging – often with expectations of reduced costs at the same time – machine manufacturers are faced with a challenge. 8 PECM Issue 17 The core of weighing and packaging processes One of the most crucial components for constructing powerful packaging machines is the load cell. Up until recently, manufacturers of checkweighers have had to rely on load cells which were based on the principle of electromagnetic force compensation (EFC), although this has been at a relatively high component cost. But there is an alternative which has been in development for some years but is now readily available: digital load cell based strain gauge (SG) technology, which offers up to 60% cost savings in comparison to load cells based on EFC. But does this new age of digital load cell technology compromise on the speed and accuracy of EFC sensors traditionally found in packaging machines? And is the arrival of digital load cells the right answer for machinery manufacturers to develop products for new markets? The hard facts Precision and speed are the two determining criteria for load cells, ultimately because both factors save cost; precision because it makes for improved safety margins, and speed because faster weighing means greater