Viewpoint: load cell digital technology fills an efficiency gap
30 Jan 2017
Load cells can save substantial costs by preventing product overfilling and avoiding penalties incurred for underfilling products, says HBM’s Thomas Langer.
By digitising manufacturing processes, the Industrial Internet of Things (IIoT) can lead to great efficiency and productivity gains in the food and packaging industries.
Digital weighing technology, in particular, offers enormous potential for determining filling quantities quickly and precisely, which can lead to major savings – several million euros annually in some cases.
Previous analogue weighing technology can also be digitised easily and reliably using transducer electronics and integrated on a single platform.
Companies in the food and packaging industries are required to comply with the provisions of the EU prepackaging directive 76/211/EEC. The German pre-packaging regulation contains clear requirements in this regard: on average, the quantity must not be less than the nominal prepackaging capacity.
Digital weighing technology, in particular, offers enormous potential for determining filling quantities quickly and precisely, which can lead to major savings – several million euros annually in some cases
This means that in practical terms, the producer is always free to overfill, but of course including less than the indicated quantity is critical.
The result of this strict regulation is that many food producers work with expensive overfilling. This can add up to major additional costs, especially with premium products such as olive oil, ice cream and cosmetics.
Underfilled products are also rejected, resulting in more expense and additional processes.
These inaccuracies can be prevented with a more precise, reliable weighing technology as early as the filling and metering phase and no later than in the checkweighers at the end of the production line.
When weighing technology is precise, it can only boost efficiency and productivity. The load cell is the crucial component in packaging machines and the core of dynamic weighing and packaging processes.
Until now, manufacturers of checkweighers have relied on load cells that work on the principle of electromagnetic force compensation (EFC). They have previously outperformed other load cells based on strain gauge (SG) technology with high precision. At the same time, however, they can be expensive, susceptible to problems, and complex to put in operation.
HBM’s newly developed SG-based FIT7A load cells are designed to ensure precision and high speed for processing measurement data, as well as easy operation and significant savings.
When weighing technology is precise, it can only boost efficiency and productivity. The load cell is the crucial component in packaging machines and the core of dynamic weighing and packaging processes
The FIT7A has been optimised for checkweighing. Together with the integrated filters and processes for determining dynamic measured values, it has been designed to contain everything necessary for dynamic weighing without the requirement of an additional PLC and weighing electronics.
This permits a checkweigher to achieve standard deviation of only 0.1g per 10kg of nominal weight. Depending on design and nominal weight, 100 to 400 measurements per minute can also be implemented.
Digital platform
HBM has developed PanelX software as a digital platform to integrate digital and analogue load cells based on the gravimetric principle into machines (gravimetric level measurement ensures that only the minimum specified product quantity is filled).
A wide range of SG-based load cells can be configured easily. The analysis functions are also helpful for finding faults that are not caused by the load cell. Extensive online help is integrated into the software via a web browser.
A new age
A large number of load cells can be configured and monitored with PanelX for almost any application. That includes the analogue load cell, PW27, designed for use in weighing systems for beverage, food, pharmaceutical and bio.
HBM has also developed PAD digital transducer electronics to make use of the advantages of digitisation with analogue load cells.
With PAD and the integration into the PanelX platform it provides, analogue load cells can have all the advantages of digitisation. That makes it possible to visualise and analyse dynamic filling and dosing applications in harsh environments, and re-regulate immediately during the process.
- Thomas Langer is HBM’s international product manager for weighing technology and OEM sensors
