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GE Fanuc's Cimplicity and PLCs are ensuring that the correct mixture, governed by the strict requirements of the building industry, is loaded on to Wopfinger Transportbeton's concrete mixing plants for the industrial weighing.
Concrete mixing plants owned by Wopfinger Transportbeton are located throughout Austria.
GE Fanuc's Cimplicity and PLCs are used to ensure that the correct mixture, governed by the strict requirements of the building industry, is loaded on to their concrete mixing trucks.
In the design of the mixing control system, particular emphasis was placed on the need to supply simple, user-friendly operation, while maintaining procedures familiar to the operating staff.
The concrete mixing plant, built in Grimmenstein in the late 1970s, was replaced in 1999 by a new plant.
The electrical and automation mixing systems were designed and implemented by the automation specialist SteKa, using the Windows-based control and monitoring software, Cimplicity HMI, and GE Fanuc Series 90-30 PLCs.
Dipl.-Ing.
Christian Steiner, General Manager at SteKa Automation und Anlagen GmbH, underlined the special circumstances of the plant in Grimmenstein: "For this project, we were in charge of the design of all aspects of automation.
As we were able to start with a clean sheet, we could develop a control concept based entirely on the latest state-of-the-art technology.
The "brain" of the new concrete mixing plant is the batching control unit designed by SteKa which controls all batching processes and weighs the batches for transportation.
At the same time, all collected data is stored in a database and a log entry automatically generated for each batch.
The batching and mixing system is designed so as to allow the entire plant to be operated by just one person.
The mixing foreman manages and monitors the raw material entering the system, the mixing itself, and then the transfer to the mixer trucks which are used to transport the product to the site.
The foreman controls the formula which is automatically allocated to each truck by material planning, and he monitors the weighing process, especially as the raw material can sometimes get blocked in the feeder.
Support for all these operations is provided on screen by the Cimplicity visualisation software and its control functions.
For instance, any exceptional weight, i.e any deviation from pre-set weights, will be immediately displayed.
In addition, circuit breakers are monitored in case of malfunctions.
Charging is also carried out automatically once the foreman has set the silo for the required delivered quantities.
The most important screen for the operator is the batching screen which displays all the batching components, the scales and the mixing unit.
The current job is shown in a small separate window.
Although the amount of data to be processed is comparatively small, the visualisation software meets ambitious targets.
As batching processes have to be monitored in real-time, all of the 600 visualisation points (one point corresponding to one data register in the PLC) have to be updated in real-time on the screen.
The SteKa database system includes the entire order planning, handling and logging, and it provides complete statistical evaluations of the order and production data.
When asked about his experience with the GE Fanuc products, Christian Steiner replied: "Soon after Windows 95 was introduced, a CIMPLICITY version was available for that operating system.
We decided to switch to Cimplicity from a rival product we used to use.
In our experience, GE Fanuc has managed to develop Cimplicity so that it has always maintained its edge over other visualisation systems.
As a matter of principle, SteKa uses, as far as possible, only standard hardware and software components for their plants - to their customers' advantage.
When it comes to weighing technology, one particular feature of the GE Fanuc PLC provides special benefits.
A flexible measuring tape is available for the Series 90-30 PLCs which allows direct connection of load cells to the controller (with no measuring amplifier required).
T and G, the GE Fanuc distributor for Austria, has proved to be a totally reliable partner for SteKa.
As Steiner explained, "On-site service is an essential prerequisite, especially for the building sector.
Due to heavy decentralisation, most of the sites only have a very limited staff.
Technicians are a rarity.
Therefore, unless we are able to locate and correct errors by remote maintenance, we have to solve any problems directly on-site.
We therefore also depend on competent and reliable suppliers who are able to provide spare parts and know-how quickly whenever such assistance is needed.
With T and G, GE Fanuc products and our know-how, we have found an ideal combination for our automated concrete mixing plant solutions.