Elten’s proven technology convinced Belgian project integrator and retailer
Being prepared to build a sample line in Veenendaal gave ABB Robotics Solutions and Colruyt the confidence that Elten would bring the project to a good end.
"Our systems eliminate annoyance and stress in people on the floor. As a result they work more pleasantly in an ergonomical sense and are more productive." This is how the board of directors introduces its company Elten Logistic Systems during a company visit in Veenendaal. As we later visit retailer Colruyt, this claim appears to be correct.
Elten Logistic Systems
Elten Logistic Systems is a Dutch family company specialist in the field of internal logistics, handling, mechanization, transport and buffering. It provides modular high-tech systems for warehousing applications. The company also designs and builds systems for the handling of e.g. roll containers, crates, pallets and – used by Colruyt – LIC’s: Liquid Ice Containers (see below).
The slogan remains the same throughout the years: "Anything you can leave out in a device, must be omitted, so it cannot break down. This view is at the heart of the Elten’s company philosophy” says Arie Achterberg, responsible for technology. "Dutch simplicity" adds his brother Hilbert, responsible for Elten’s daily affairs.
Their father Gert founded Achterberg Besturingstechniek in 1986. The company designs and elaborates complete solutions in the field of control technology. Achterberg acquired Elten - nowadays a company with 40 man staff - years ago. The project organization fluctuates in size, depending on the order volume. "We are flexible as to manpower. We put out a lot of work to local entrepreneurs the family has known for years. We innovate where we can, look at the latest technology and integrate that – as far as possible – into our systems".
The company’s floor space is also growing steadily. "This space is needed, because it must accommodate the solution that we have worked out for our customer's problem. It is extensively tested and finally approved by our customer. We also did so with regard to the logistic installation for Colruyt in Belgium", says Arie.
Hilbert: "First we list the needs of our customer. Then pre-engineering takes place until we come up with a good solution. After that, mechanical and electrical engineering and software engineering follow. After the customer’s consent, the parts are manufactured by third parties, and then assembled, wired and tested at Elten. We make the control cabinets, cabling and software ourselves. When all this is done, the customer comes along and assesses the test with his own products. After that, disassembly and transport are taken care of. We deliver within Europe, but also in Australia and for example in the United States of America." Arie: "There are competitors at every point in the chain, but on the whole we are unique".
Elten, client of ABB Robotics Solutions, project integrator
ABB Robotics Solutions is a strong player in the field of warehousing & logistics. The company develops solutions for production and logistics (Automated Material Handling Systems). In this capacity, ABB Robotics Solutions is ultimately responsible for the project that was carried out at Colruyt. For this project, ABB Robotics Solutions engaged our customer Elten Logistics Systems.
Colruyt is the largest and most famous supermarket chain in Belgium, founded in 1928 as a family business. It has a motto – a guarantee – that will appeal to many Dutch people: "The lowest price, for every product, at any time". In order to fulfil this promise, Colruyt must pull out all the stops to minimize costs.
We are Melis Dekker’s guest, software engineer at Elten. Together with other Elten colleagues, he has worked at the installation of a new logistic system in the distribution centre (120,000 m²) of Colruyt for more than 10 weeks.
Quote from Melis Dekker, software engineer at Elten
Colruyt’s decision to take its chance with us, Dutchmen, via ABB Robotics Solutions, is based on Elten’s proven technology. Our technology gave them the confidence that we could bring the project to a good end.
Colruyt Group has thousands of Liquid Ice Containers (LIC): in-house designed and developed carts in which fresh products are cooled by means of liquid ice during transport. This liquid ice is a frozen, but liquid mixture of water and a saline solution that Colruyt itself developed. The liquid ice is pumped into the walls of the LIC and reaches the desired temperature within 30 minutes. This creates a coolness chain of at least 32 to 50 hours (dependent on the type of products, weather conditions…), from the injection in the LIC to the shelves of the supermarket. It guarantees that the products remain fresh. The LICs are transported to supermarkets in ordinary lorries. When the trucks return empty, the melted ice is extracted from the LIC, cooled down again (by means of green power from own wind turbines and solar panels) and reused in a subsequent LIC.
Colruyt's unique strategy
By using the LICs, Colruyt is able to distribute its products – frozen, fresh and dry – by means of regular trucks. Fully cooled, and therefore expensive, trucks are not needed, because the LICs are simply placed next to the dry goods. Furthermore, no long routes need to be driven to be profitable. In addition, double transport is not necessary, making transport more efficient: In 99.5% of cases, the trucks are fully loaded. And because the LICs remain cool for up to 48 hours, transports are also planned more flexibly and efficiently. There is more margin in returning to the distribution centre after delivery, thus more flexibility in the logistics chain and less greenhouse gas emissions. This shows Colruyt’s efforts to combine innovation and sustainability.
Arie: "We have quite some experience with SEW, being one of our established suppliers of electric actuators and inverters. Our programmers know the software. SEW is accepted by customers, so we have no discussions on that. We have the knowledge and the quality is good. In addition, it is convenient that SEW is present and available worldwide, for example for the delivery of service parts."
In order to realize the Colruyt project, Elten submitted an inquiry for among other things 52 MOVITRAC® frequency inverters in a central configuration. However, SEW managed to convince Elten of a decentralized concept and to implement the drive system with 52 mechatronic, decentralized MOVIGEAR® IE5 drives. Arie: "The project was suitable for it. Due to the MOVIGEAR®’s large control range we were able to limit ourselves to just three types of motors, despite the fact that the output track had to be heavier in terms of drives. We could reduce the control cabinet. Testing was possible in Veenendaal without control cabinet ".
Decentralized concept, what does it involve actually?
Paul in't Hout, sales engineer at SEW-EURODRIVE: "In the technical sector, staff are scarce. The trick then is to do the same work or more with the existing staff. One of the ways is saving on time and cabling. By means of modular machine building, the construction of a complete machine is prepared at the home office, whereafter the ready-made modules, including cabling, are built up at the customer’s location. In this way we limit the time for installation and assembly by mechanics at the customer’s site, for instance, for mounting cables from of each drive to a central control cabinet. With plug connections we connect everything quickly. This will also lower the costs."
Instead of placing the inverters in a central control cabinet, these are located locally on the motor, in the field. The decentralized modules are interconnected, which saves a lot of cabling. Paul: "In the Colruyt application we reduced the number of cables from the control cabinet to the engines from 156 to 24. As a result the control cabinet could be made much smaller. The modules were provided with cables in advance, which resulted in less installation time and less costs on the spot. Paul: "In summary, our solution is: By using decentralized and modular control and drive technology, the inverter is placed on the motor and this means: shorter installation time, smaller control cabinet, simple start-up, despite increasing complexity of the installation."
Quote from Arie Achterberg, responsible for technology
Using the decentralized concept, we can now determine up to the sensor/photocell level which part is malfunctioning. So we get better feedback from failures via remote I/O. That's a big advantage.
Hilbert: "We are now growing 10% per year without active acquisition. In 10 years we expect a doubling in turnover and staff. Our machines often make manpower redundant. As soon as the return on investment is good, we also expect growth in countries that now have less expensive workforce. We are already prominently present in high wage countries. USA is a growth market, because there is still a lot to be automated."
The Liquid Ice Containers are shared out among six filling stations. At the filling station the LIC is filled with liquid ice. There are five conveyor belts per filling station that import the LICs and put them on a shuttle. The shuttle places the LIC on one of the four buffer and/or output tracks.
Since the LICs are brought to the next position each time, they must be positioned with each movement. For this reason, the MOVIGEAR® drive is equipped with an encoder. The MOVIGEAR® gets a new position assignment from the PLC via ProfiNet. The encoder is handled internally in the MOVIGEAR® and therefore must not be connected externally. This obviously saves quite a lot of cabling in this project. The momentary position is fed back to the PLC via ProfiNet.
At the MOVIGEAR® a minimum of two cables are connected: One for the supply voltage and one for communication (in this project ProfiNet). As an option, the 24 V power supply is also connected for this project. The signals are looped from one MOVIGEAR® to the next. For this type of projects, where the motors are positioned at a greater distance from the control cabinet, loop-wiring can save on cables considerably. Due to the looping, the decentralized concept is an ideal building block for modular machine construction.
The MOVIGEAR® meets the highest energy standard IE5 and therefore also ensures maximum energy savings.