The greater the task, the more important solid preparation is. The automation specialists at the Stoll Group, based in the Oberallgäu region of Germany, are standardizing 130 PLC controllers across five Champignon dairy sites. Their solution sets new standards in efficiency and programming quality.
Developers at Stoll worked closely with the Champignon Hofmeister Group to thoroughly prepare for this major project spanning five production sites over the next few years. Since such large parts of the code for individual subprojects can be generated fully automatically, both companies benefit equally: from greater cost efficiency and higher code quality to a transparent code structure, both now and over the entire life cycle of the solution.
After the scope of the customer project had grown over the course of 2022, the specialists at the Stoll Group began looking for a solution in early 2023 that would ensure the long-term structured and uniform generation of the code and also enable the fully automatic generation of essential parts of the code. Since SIMATIC S7-1500 controllers were installed at the customer’s site and a solution based on the pure TIA Portal Openness interface was rejected due to the complexity of the project, the team led by Andreas Krug and Thomas Bilgri from the Automation Competence Center (CCA) at Stoll Automation GmbH decided to develop a customer-specific equipment module based on the SIMATIC Modular Application Creator Module Builder.
The software enables the automated creation of TIA projects and, thanks to the included comfort functions, makes it much easier to use the Openness interface especially when generating software. Andreas Krug, Head of CCA Software Construction & Commissioning at Stoll: “The idea was to reduce the amount of manual programming in the TIA Portal with the customer-specific equipment module. This would minimize sources of error and create a recognizable basic structure for all individual projects.”
Up to 66% of the PLC base code is generated fully automatically, reducing manual programming, minimizing sources of error and ensuring consistent code quality across all 130 controllers.
One customer-specific equipment module standardizes 130 PLC controllers across five production sites, ensuring consistent code quality throughout the entire project lifecycle.
By automating the generation of PLC base code, Stoll completes projects up to three times faster than with fully manual programming, without compromising on code quality or structure.
In the automatically generated code, the various program parts or instructions are always in the same place. Once you understand this system, you can work much more efficiently, both in programming and later on in service.
Until that point, the programmers first had to program the equipment module themselves in close cooperation with the Engineering Workflow Systems Consulting and the Application Center from Siemens – which, of course, was not done at the PLC programming level, but with C-Sharp. Thomas Bilgri, CCA software engineer at Stoll: “We don’t use high-level language programming like C-Sharp every day. But the more time we spent with it, the more clearly we could see the potential of the Modular Application Creator. In fact, we were able to use the Modular Application Creator as a code generator in less than three months.”
The customer-specific equipment module has been in operation since August 2023, and since then Stoll’s automation team has been working on refining the module and implementing the first projects. The basis for the programming is a flow diagram or a reference indicator list of the customer’s system in question. “From this, we develop a structured XML file with all the motors, valves, sensors, etc., and generate the basic PLC code for the system using the equipment module and the Modular Application Creator,” says Thomas Bilgri.
By using the Modular Application Creator to automatically generate the PLC base code, we are able to program much faster, and we benefit from a consistently high code quality
The work is not done yet. “But,” says Andreas Krug, “the basic code is generated cleanly. This saves time, reduces sources of error, and ensures that the basic structure of the software is the same in all projects.” Krug estimates that the percentage of automatically generated code, which was already 50 % in the first subproject, will rise to 66 % in the long term – a value that can be translated almost one-to-one into time saved: “I have just designed a system where the generated basis was available – and I would say that if we had had to create all this manually, it would have taken us three times as long. And if you consider that we are talking about around 130 controllers in total, you can easily calculate the benefits that structured and automatic code generation offers us.”
The associated reduction in programming costs is only one advantage offered by the customer-specific equipment module. The qualitative dimension is at least as important for the developers: “Because the basic code is generated by one and the same code generator throughout the entire project,” says Bilgri, “the PLC software is structured in the same way for each system. This facilitates the division of labor in software development because everyone knows where to go. It also supports code modification after the fact, because revised software building blocks can be easily replaced anywhere, and it simplifies maintenance throughout the entire lifecycle of the solution, because everyone knows where the functions are hidden.”
Thanks to the standardized program structure, we benefit not only during commissioning, but also during service – this saves time, reduces sources of error, and offers us numerous economic advantages throughout the entire project.
In addition – and this is crucial for a medium-sized company like Stoll – a project of this magnitude would hardly have been possible for the Allgäu-based specialists without the customer-specific code generator, especially in light of the shortage of skilled workers in the industry. Andreas Krug: “This would not have jeopardized the trusting relationship we enjoy with our end customer, which has grown over 25 years, but it would have put it to the test.”
Speaking of the Champignon dairy, the company’s in-house technicians and process specialists are enthusiastic about the highly structured software. “Thanks to the standardized program structure, we benefit not only during commissioning and service, but also with the visualization interface or when connecting the systems to higher-level control systems. This saves time, reduces sources of error, and offers us numerous economic advantages throughout the entire project,” says Andreas Kuisel, Head of Electrical Engineering at the Champignon cheese dairy.
Based on the positive experience with the Champignon dairy project, we decided to use the Modular Application Creator to develop our own standard in-house equipment module. This will enable us to complete cross-industry projects with our customers efficiently and with a high level of quality.
It is therefore not surprising that in early 2024 the decision-makers at Stoll Automation GmbH decided to go beyond the equipment module now developed, which addresses both industry-specific and customer-specific requirements, and to additionally develop Stoll’s own in-house equipment module “that will enable us to complete their own projects efficiently and with high quality across all industries,” says Michael Mildner, Member of the Executive Board and Head of the Automation Competence Center (CCA) at Stoll. “In addition, we want to use the wide range of functions of the Modular Application Creator not only at the PLC level, but also on the HMI side and in the higher-level control systems.”