Interview with Dr. Josef Papenfort and Béla Höfig on the leap in performance brought about by TwinCAT PLC++
Based on well over 40 years of experience with state-of-the-art automation technology and almost 30 years with TwinCAT software, Beckhoff has developed a new generation of PLC technology in the form of TwinCAT PLC++. In this interview, TwinCAT product managers Dr. Josef Papenfort and Béla Höfig explain the performance leap this enables in terms of both engineering and runtime.
A new generation of PLC technology – what does this mean for automation engineers already working with TwinCAT?
Dr. Josef Papenfort: TwinCAT PLC++ is based on the familiar TwinCAT architecture and is fully integrated into the proven TwinCAT ecosystem. Complete compatibility with the existing TwinCAT Functions is ensured and the new PLC generation can also be used in parallel with the existing TwinCAT PLC if required. For example, existing TwinCAT Scope and TwinCAT HMI applications can continue to be used unchanged. The available PLC libraries can also be used to their full extent. On the one hand, this enables a step-by-step changeover with parallel TwinCAT PLC and TwinCAT PLC++ operation. On the other hand, an integrated converter enables the efficient transfer of existing program code, so that existing expertise is easily available in TwinCAT PLC++. Switching therefore involves little effort.
What will change with TwinCAT PLC++ in terms of technology?
Béla Höfig: TwinCAT PLC++ is a completely new development from Beckhoff, but of course it is still based on the languages described in IEC 61131-3. Due to aspects such as the modern compiler technology and the new architecture used in this context, a significant leap in engineering and runtime performance can be achieved. Beckhoff is consistently pursuing the path of converging automation and IT that it has taken from the very beginning. Although the company has retained familiar and proven features, it has redeveloped key components of the development environment such as editors and compilers based on best practices from IT. What’s more, Beckhoff has placed particular emphasis on the possibility of using DevOps principles to implement continuous integration and continuous deployment, and focused particularly on the specific needs of users. This results in a PLC that is not only extremely advanced in terms of technology but also perfectly tailored to requirements in the field.
What performance gains can be achieved in terms of runtime?
Dr. Josef Papenfort: Compared to the previous version TwinCAT PLC, the same control code can be executed up to 1.5 times faster during runtime. And as a special highlight, the new TwinCAT PLC++ compiler makes it possible to further optimize the control code in terms of execution time and thus achieve an overall performance gain of up to a factor of 3.
What are the concrete advantages for machine builders and users?
Béla Höfig: The significantly faster execution of the control code generates different advantages depending on the machine requirements. For example, an industrial PC with less computing power may be sufficient for the previous machine control application, which reduces hardware costs. If the hardware platform remains unchanged, the freed-up computer resources can be used either to implement more control functionality or to increase the productivity of the machine by minimizing cycle times.
To what extent does control engineering benefit from TwinCAT PLC++?
Dr. Josef Papenfort: From an engineering perspective, TwinCAT PLC++ achieves shorter throughput times from control software development through to commissioning and the entire machine life cycle. This is achieved by reduced operating times through shorter project loading times and an improved compile process. The minimized project load times significantly reduce costs and also enable new machines and systems to be launched more quickly.
Béla Höfig: Furthermore, the new TwinCAT PLC++ architecture enables an even deeper integration of TwinCAT Functions. For example, TwinCAT HMI and TwinCAT Target Browser can access the PLC variables directly without the program code having to be compiled ready for execution beforehand. In addition, a programming assistant based on TwinCAT Chat can be integrated. This assistant can support the generation of both textual and graphical codes. There are also expandable code snippets, smart shortcut functionalities for guided code creation, an online-offline code comparison, and a favorites pool. In this way, the extensive potential of the TwinCAT world can be fully exploited and the entire engineering process can be made more efficient.
Dr. Josef Papenfort: In addition, the program code is stored in plain text at file level for the first time. This simplifies the use of source code management systems such as Git, as comparing different code versions is particularly easy and intuitive. What’s more, the new compiler is available as a stand-alone component and can be called up automatically via a command line interface. Given that a complete engineering instance is no longer required, this allows automated processes for creating and testing program code in unit tests to be greatly optimized in terms of time.
How well does TwinCAT PLC++ perform with regard to standard conformity and code quality?
Béla Höfig: As a member of the German IEC group, Beckhoff has a direct influence on the latest developments and best practices in standardization. TwinCAT PLC++ is almost fully compliant with the fourth edition of IEC 61131-3 and meets the highest international standards. With the resulting portability, it facilitates exchange and collaboration between different automation systems. In addition, it is possible to use standard-conforming object orientation with classes and access modification for variables, among other things. Compliance with the IEC standard offers additional safety aspects for programming, which are supplemented by extended type checks in the compiler. TwinCAT PLC++ also offers a secure online change where pointers and references are automatically adjusted. This prevents the implementation of potentially error-prone code and ensures that the application is more reliable and secure – resulting in better code quality overall.
TwinCAT PLC++ was presented at the SPS 2024 trade fair in Nuremberg. What was the feedback like and what is the roadmap for the future?
Dr. Josef Papenfort: The initial reactions and assessments from both customers and market players were extremely positive. We are now working hard on further functions and optimizations so that numerous new features will be available in time for Hannover Messe 2025. The software release is scheduled for the end of 2025.
