What is Codesys?
Codesys (Controller Development System) is a software development environment for programming PLCs and automation systems, developed by German company 3S-Smart Software Solutions. It is the world's most widely used IEC 61131-3 runtime and programming environment: more than 500 hardware manufacturers use it as the basis for their controllers, from industrial PLCs to embedded systems and motion controllers.
Unlike proprietary environments such as TIA Portal (Siemens) or Studio 5000 (Rockwell), Codesys is manufacturer-independent: once you master the platform, you can programme controllers from Wago, Schneider, Pilz, Festo, IFM, Phoenix Contact, Beckhoff and hundreds of other manufacturers without needing to learn an entirely new environment for each brand.
IEC 61131-3: the 5 programming languages
Codesys fully implements the IEC 61131-3 standard, which defines five programming languages for PLCs: LD (Ladder Diagram), FBD (Function Block Diagram), ST (Structured Text), IL (Instruction List) and SFC (Sequential Function Chart). In a single Codesys project you can mix all languages, choosing the most appropriate for each part of the programme.
Which manufacturers use Codesys?
- Wago: the entire PFC100 and PFC200 controller range uses Codesys 3. Very popular in building automation, energy and water cycle.
- Schneider Electric: Modicon M241/M251/M262 PLCs programme with EcoStruxure Machine Expert, based on Codesys 3.
- Pilz: the PSS 4000 safety controller uses Codesys Safety.
- IFM, Phoenix Contact, Festo, Bosch Rexroth — all base their controllers on Codesys runtime.
- Beckhoff: TwinCAT shares a foundation with Codesys but is an independent branch with proprietary extensions (C/C++, advanced Motion Control).
Codesys vs TIA Portal: key differences
| Feature | Codesys | TIA Portal (Siemens) |
|---|---|---|
| Manufacturer independence | ✅ 500+ manufacturers | ❌ Siemens only |
| Programming licence | Free (Codesys Development System) | Free (limited Basic) |
| Built-in visualisation | ✅ WebVisu native | ✅ WinCC (separate licence) |
| Motion Control | ✅ CNC and robotics | ✅ (requires Technology CPU) |
| Ecosystem maturity | Wide but fragmented | Very mature and unified |
When to choose Codesys?
- When you don't want to depend on a single hardware manufacturer
- Projects with Wago, Schneider M2xx or IFM hardware where Codesys is the native runtime
- Applications needing web visualisation without SCADA licences (WebVisu)
- Machines that will be sold to customers with different PLC standards
- Complex Motion Control projects on Codesys-compatible hardware
At Bluemation we programme Codesys in real industrial projects. Contact us if your project uses Codesys-compatible hardware.