Software-defined automation adds ladder logic and reaches more users
18 June 2026 
Siemens is making software-defined automation (SDA) accessible to a wider range of users – including service and maintenance teams – with enhancements to its Simatic AX Logic Control Engineering (LCE) engineering tool. The changes include the introduction of a ladder programming capability, the first graphical programming language for LCE, and support for Siemens’ Simatic S7-1200 G2 compact hardware controllers.
The updates combine OT-friendly programming with IT-style workflows, helping engineering teams to work more efficiently, while opening up new application areas for basic automation projects where cost-efficiency is paramount.
Until now, Simatic AX LCE has been an engineering environment based on Structured Text (ST), aimed primarily at software automation engineers. The addition of the ladder programming environment, called XLad, means that service and maintenance technicians, as well as engineers who prefer graphical logic representation, will be able to work more intuitively with control programs.
Siemens says this will shorten onboarding times, simplify troubleshooting, and improve collaboration because more users, both from OT and IT, will be able to participate and collaborate across automation workflows.
“By introducing ladder programming to Simatic AX Logic Control Engineering, we’re making software-defined automation more accessible to a broader user base from the world of operational technology – bringing the digital and the real worlds closer together”, says Rainer Brehm, COO for automation and CTO at Siemens Digital Industries. “This creates new opportunities for efficient engineering, maintenance and collaboration.”
XLad is the first text-based ladder programming tool to be integrated into the Simatic AX LCE environment. It brings software development practices such as version control, automated testing, and continuous integration, into the world of ladder logic. With integrated support for Git and CI/CD (continuous integration and continuous delivery/deployment) workflows, users can manage changes to ladder logic more transparently, collaborate more effectively across teams, and increase software quality in engineering.
The seamless interaction of XLad with ST will allow users to re-use libraries created in ST by integrating them into ladder logic applications. The object-oriented programming and intuitive readability of ladder diagrams make it easier to implement complex control logic with unprecedented clarity and efficiency, according to Siemens.
In addition, XLad supports bidirectional programming. Users can switch between a graphical view and a text-based editor, depending on their workflow preferences. The textual representation is both human-readable and AI-ready, laying the groundwork for future AI-supported engineering applications, such as AI-assisted development of control logic. Furthermore, text-based representation is the basis for easy version management using Git.
At the same time, Siemens is extending the hardware scope of Simatic AX LCE by adding support for its Simatic S7-1200 G2 basic controllers, thus opening up a new spectrum of projects that can be solved using Simatic AX LCE. Previously, the Simatic AX tool focused on supporting Simatic S7-1500 controllers. Now, users can also apply Simatic AX LCE to the engineering of basic automation controllers.
