Safer travel for “bucket conveyors” in the production of precast concrete elements
When laying grey cobblestones in road construction, probably only a few people realize that this is the serial product of a highly automated industrial process! But that is exactly how it is – and PROFIBUS, PROFINET, and PROFIsafe are also involved, including wireless connections. The effort to achieve cost efficiency and quality assurance has also led to modern production methods in the construction industry with a strong emphasis on automation technology. This is exactly the field in which the German medium-sized company Bikotronic – located in the wine-growing region of Deidesheim (Rhineland-Palatinate) – is extremely successful.
Early use of PROFIBUS or PROFINET
Bikotronic is one of the world’s leading manufacturers of control systems for the clay and bulk material industry: automation technology, self-developed dosing and measuring technology as well as software solutions are combined in a customer-specific way to form economical overall solutions. Bikotronic relies on an S7-based control technology, which has been using PROFIBUS DP as a communication technology since 1993. It was then rapidly converted to PROFINET from 2017 onwards, for which its generally high performance and not the higher transmission speed was decisive. Whether in the production of paving blocks, pipes, prefabricated parts, or ready-mixed concrete, all applications involve controllers, sensors, measuring devices, drives, frequency converters, and machines being combined in a single system via PROFINET. Due to the often large spatial expansion of the plant, the structure of the associated control cabinets is implemented decentrally. Depending on the plant, 15 or more control cabinets are distributed across the plant and connected to one another via PROFINET. The entire plant is operated centrally from a control station.
Bucket conveyor requires wireless and stable communication
The concrete mass, mixed according to the customer’s order, is transported within the production hall by a bucket conveyor running on rails fixed to the hall ceiling. Several buckets are used, all of which are equipped with their own “on-board” control systems. These have a high functionality regarding the handling of the buckets amongst themselves as well as an extremely flexible connection to the individual mixing processes and the different processing machines. Furthermore, these control cabinets contain all electrical equipment for driving the motors and for controlling the bucket functions, including the braking function to avoid collisions. The correct positioning of the buckets before they are emptied is particularly important. Therefore, counting mechanisms are used, which are continuously adjusted between the slave controls on the buckets and the master PLC in the control room. These extensive communications must be wireless due to the movement of the buckets.
Wireless PROFIBUS and Wireless PROFINET as a solution
For many years, Bikotronic has been using DATAEAGLE (DE) radio modules from Schildknecht AG to set up wireless communication links, whereby the DE3000 series is designed for PROFIBUS data transmission and the DE4000 series for PROFINET data transmission. The DE 3712 and DE 4712 modules are additionally optimized for the PROFIsafe safety protocol. They are therefore suitable for safety applications, such as those that occur in interaction with the bucket conveyor. Bluetooth is used as radio technology.
Identify and meet user needs
In automation technology, a future trend is undisputed: More and more data is being collected by more and more sensors in often difficult to access or moving environments, and must be safely transmitted to a receiver! It is a challenge for which wireless PROFINET / PROFIsafe technology offers the best solution. Bikotronic recognized this very early and used it to expand its market position. Marco Bechtold, head of project planning at Bikotronic, comments: “Our business success is based on two main approaches: (1) We pay very close attention to the needs of our customers and the local conditions at each project, and (2) we use the best possible technologies for the implementation. This led to the very early use of PROFIBUS and PROFINET and the DATAEAGLE wireless solutions.”
Wireless PROFINET and PROFIsafe in the configuration shown here not only ensures high quality of paving stones and other building components, but also stands for a mature and powerful technology for countless applications in automation technology; the solution from Bikotronic is a very good example of this.
Elena Eberhardt
Schildknecht AG