Making decanter centrifuges and other sophisticated equipment easy.

The new iX from Beijer Electronics helps Peter Blomberg and his automation colleagues to create a graphical interface that makes decanter centrifuges and other sophisticated equipment from Alfa Laval as easy to use as today’s mobile phones. The user-friendly interface is appreciated by customers, as well as the new HMI solution saves time and money in installation and service.

Australia – it says on the consignment note of decanter centrifuge just being packed into a large wooden box. High quality is one of the reasons why the machines from Alfa Laval´s production plant in Søborg, (DK), are exported successfully to all over the world.

Peter Blomberg has been three years as automation manager at Alfa Laval. He explains that the company puts a great pride in producing reliable and cost-effective machines with a long life time. The strategy also includes that their machines must be easy to use: ‘The goal is to make our machines just as intuitive to use as today’s personal computers and mobile phones’.

After arrival and installation at the Australian buyer, the decanter is operated from a Beijer Electronics 15-inch touchscreen panel. In order to function even in dusty and damp industrial environments, the panel is fitted with an IP67 seal at the rear.

Simplicity in operation
Simplicity in the operation of machines is both a selling point and a quality issue for Alfa Laval. And the latest tab-based graphical user interface 2Touch, created with the help of the iX Developer, is in perfect line with the fundamental intentions. ‘The idea is that all information should be readily available when it´s needed’.

By pressing a finger at any of the tabs on the screen, the operator open menus to see operational data, adjust parameters, acknowledge logged alarms or maybe change the menu language. Yellow labels for each choice, explain the different hand grips.

On the screen, icons to start, pause and stop, has the same symbolic language as on the DVD player in your living room. A few clicks on the screen are enough to browse through the electronic manual that describes the machine, or to see an instructional video. Alfa Laval is without doubt inspired by more consumer-oriented products and is now in the lead with increased ease of use. Peter Blomberg is clear on why this effort has been made. ‘HMI solutions with different colored push buttons and cryptic text messages on oversized screens belong to yesterday’.

While the simplicity is quite obvious, he is open about the challenges to get this far. The decision to update the automation platform, while creating the new graphical operator environment was taken before the launch of iX – Beijer Electronics’ largest and most ambitious development effort. ‘By starting in an early stage, we have not only gained a unique knowledge, but also a significant advantage over our competitors’.

Already more than fifty models of the new generation of decanters with the new user interface have been delivered to customers globally. Decanter centrifuges are not the only machines equipped with 2Touch: ‘Other types of machines in our three product areas (heat transfer, separation and fluid handling machines) will be upgraded to the new platform’.

Evaluation of more than a dozen different HMI concepts
Although there have been teething problems to overcome, He does not regret that Alfa Laval was early with iX. The decision was well founded. The project began with nine intensive month´s evaluation of more than a dozen different HMI concepts. ‘No other vendor could offer the same features and graphic possibilities within the framework of an open architecture’.

Alfa Laval has customers and employees spread all around the world. Another important issue in the selection was also the fact that Beijer Electronics is a well established and globally active company with a strong focus on technology.

Customizing to Alfa Laval’s visual identity
The development tool iX Developer is a well structured tool for configuration and documentation. Deeper HMI experience is not necessary to create a basic application in the Windows environment – something that actually does not need to take more than a few minutes.

Existing projects can be reused. In addition to this, Beijer Electronics also offers a range of ready-made and tested icons and modules. Companies, unlike for example Alfa Laval, who does not want to create custom icons, can benefit from the comprehensive component library’s standard set. ‘We have put a lot of work to customize the interface to our visual identity’, says Blomberg, ‘who among other things appreciates the vector graphics capability to create crisp, clear images at any magnification’.

In addition to openness and graphics, the flexibility speaks for iX. He notes that the HMI solution works with most control systems. This is unlike the competitors that were evaluated, where the link between HMI and PLC products often were very dense. ‘Although we are currently using controllers from B & R, the flexibility is crucial to us. Customers may have existing control systems or requests for other PLC brands or industrial computers’.

The support for OPC, provide completely freedom to choose communication protocol. This is significant in cases where Alfa Laval’s products are integrated with equipment from other suppliers in the same process line. Switching between different protocols is actually possible in real time.

A technology shift with more advantages
The decanter centrifuges touch panel facilitates not only the operator’s work through improved overview of the process. The technology shift is also an advantage for Alfa Laval’s technicians: ‘End-users are satisfied and at the same time as we obtain simplified installation and maintenance services,” according to Blomberg , “time is money, if a machine fails’.

Today Alfa Laval’s engineers reach all functions and information via the operator panel. It is no longer necessary, as before, to connect a laptop by cable for troubleshooting. Updating a machine’s system software is as easy as to put a memory stick in panel USB connector. The ability to monitor and address the machine or process line remotely via modem is another plus value. ‘With an aesthetically pleasing HMI solution that works today and has a modern feel in the years to come, we have reached our goal’, he summarizes.

Operator panels with 2Touch make even other machines from Alfa Laval easier to manage. In addition to separators and decanters, other products for cooling, heating and fluid handling belongs to the company’s range of bestsellers.

Constant development
Decanter centrifuges consist of a rotating screw conveyor that separates solids from liquids. The basic idea is the same as in Gustaf de Laval’s classic separator which for more than one hundred years ago formed the foundations of the company. Alfa Laval has over the years evolved into a publicly held global company with 11.500 employees, twenty production units and a turnover of around 26 billion SEK.

The decanter is adapted to different process environments by varying the design, height, etc. The difference between a decanter and a separator is the ability to separate out larger particles. Application areas include everything from dewatering of sludge in sewage treatment plants to food and oil production.

RTU products supports remote communication such as IEC60870, IEC61850, SNMP, Modbus.

Level detection of foaming media

 

Accurate and repeatable point level measurement using electromagnetic waves

Thick & Creamy!

What coffee connoisseurs love about their latte macchiato is the thick, creamy milk froth on top of their drink. However, in many processes, frothing appears as an undesirable side effect that can lead to problems if it influences the level measurement. Ideally, the sensor would ignore the foaming, as it does with the level switch LFFS for point measurement, sensing using electromagnetic waves, which only reacts after the actual liquid level has been detected.

Foaming – a Challenge for Level Measurement

Although seen in many fields of daily life – just think of a hot bubbly bath or the tempting froth on fresh beer – foaming poses a challenge in process measurement, for example in the brewing, fruit juice or milk industries.  Point level detection in tanks is one of the most common applications in the process industry, making use of a number of point level switches based on various technologies. The technologies’ suitability depends on the application and external standards or approvals requirements. High hygienic standards have to be met especially in the pharmaceutical and food and beverage industries, where approvals like 3A, EHEDG and FDA certifying the devices’ hygienic capability regarding their design, construction and material, are essential.In many processes in these industries, the foam forming on the surface of the rising or falling liquid level would be detected by an ordinary level switch, which would operate even though actual liquid level had not yet been reached. Erroneous level measurements caused by false minimum or maximum level indications lead to process downtime or production quality problems.

Level switches by Baumer

Baumer's LFFS sensor

For applications like these, Baumer offers the LFFS designed especially for the use in hygienic processes. With its factory supplied configuration the level switch will detect the difference between foam and any aqueous liquid. Additionally, by using the configuration tool FlexProgrammer 9701, the adjustment of switching sensitivity, response time and output options, allow precise measurement parameters to be set. Prevention of erroneous level measurements using the LFFS allows productivity to be increased, quality improved and financial efficiencies realised.

An operating principle based on electromagnetic waves

A high-frequency signal sweep is radiated from the sensor tip into the tank. The media will act as a virtual capacitor, which together with a coil in the sensor head, forms a circuit creating the switch point signal. This virtual capacity will depend of the medium’s dielectric value and is well defined for most media. The switching function – whether open or closed – can be realised by changing the type of connection or by use of the FlexProgrammer 9701. The output type can be chosen as PNP, NPN or digital out by the programming unit. A damping of the output signal can be activated in case of a fluctuating media level, e.g. during the tank filling.

The advantage of the LFFS technology lies in the fact that only the very small conical measuring tip needs contact into the media. With other technologies the sensor requires a bigger surface contact into the media which viscous or adhesive media can easily adhere to causing switching errors. Whereas with the LFFS the small wetted surface of the sensor is highly resistant to media adhesion.

A special 3A welded socket ensures the hygiene-approved mounting into the process tank, and further offers the advantage of a drilled port to show leakage past the measuring tip that would consequently cause a dead-space contamination problem.

Welded socket with drilling

LFFS with cooling neck

The device’s 3A approval is only valid in conjunction with a 3A approved tank mounting connection – in this case a welded socket. All components in contact with the media to be measured are made of acid-proof high-quality steel or PEEK thermoplastics and fulfil the FDA, 3A and EHEDG regulations. The device is available with various 3A-approved process connections.

The LFFS measures the limit value of fluids (e.g. water, beer, milk); viscous and even dry substances (e.g. ashes, flour or grain). Already factory preset and without any further adjustment, the LFFS detects the level of aqueous fluids, liquids, viscous fluids and even dry media. For particularly difficult media like adhesive substances, the teach-in function enables a manual adjustment of the level switching point to be programmed.

A 360’ visible high intensity blue LED on top of the LFFS indicates when the switch point is reached, with the switching status user programmable to normally open (NO) or normally closed (NC). The indication can be seen easily even if the sensor is mounted on top of a tank. Operation is unaffected by vibration or turbulence in the media. Since the mounting position does not affect its performance, the sensor can be installed sideways or at the bottom of a pipe as used for pump dry-run protection.

For use in closed tanks the device withstands a pressure of up to 40 bar. Since the level switch does not contain any moveable parts and its electronic unit is completely integrated, it is maintenance-free offering a high reliability and low cost of ownership.

Crème Fraîche

Youghurt!

In the standard version, the level switch is designed for permanent process temperatures from  -40 °C up to +85 °C. However, it is suitable for the use in CIP and SIP facilities with short-term temperatures of up to 140 °C for a maximum of one hour. With an optional 100 mm or 250 mm cooling neck, the LFFS can then be used continuously at process temperatures of up to 200 °C. The cooling necks are designed with sliding connections and can therefore serve as an extension, e.g. if the sensor tip has to reach deeper into the tank, or if the media has to be reached through a tank insulation.

Applications in the food industry

The hygienic LFFS models are used primarily in the food and beverage industry. At Denmark’s largest yoghurt dairy, in Brabrand, Arla Foods uses the LFFS in the balance tanks of different filling machines for high and low level detection. In one case the medium is yoghurt, in the other it is Crème Fraîche, a heavy cream with 10 to 38 % fat content. Both media are very viscous and adhere to the measuring devices. Arla Foods has removed vibrating tuning fork type switches because their function and switching was affected when the media adhered to the forks which led to incorrect measurements. These were replaced with LFFS that now detect the level accurately and reliably.

Further principles of level measurement

In addition to the LFFS, Baumer offers their customers optimal solutions and technologies for most level measurement applications, utilising a wide range of continuous and point measuring level devices based on various technologies, including differential pressure; potentiometric; capacitive; ultrasonic and optical. These are variously available for contact or non-contact as well as side-view mounting.