Virtual Fieldbus Simulator can simulate TwinCAT/ADS ports and services. In virtual ADS the port (entry point) and all AMS services are simulated by independent EVA ICS deployed services.

Virtual TwinCAT/ADS

Virtual TwinCAT/ADS documentation

Supported features and limitations

EVA ICS Virtual Fieldbus Simulator ADS service is the most complete TwinCAT 3 ADS simulation on the market which can be used for various testing and studying scenarios such as automated CI/CD.

  • The majority of ADS types are supported

  • Arrays, including ranges, are supported in the same way as in real TwinCAT 3

  • Most of ADS commands are supported, including SUM read/write/read-write.

  • ADS services try to fully emulate ADS context, including variable information tables etc.


  • Notifications are not supported

  • Complex structures are not supported, meaning MAIN.struct.var1 and MAIN.struct.var2 are two different variables.

  • Arrays of structures are not supported, meaning MAIN.struct[0].var1 and MAIN.struct[1].var1 are two different variables. Consider adding both.

  • AMS routing to client side is not supported. This can be considered as a feature, as virtual ADS ports allow multiple applications to connect from the same host. Keep in mind that in production the applications must respect the real AMS routing requirements.


TwinCAT is the registered trademark of Beckhoff Automation GmbH. Virtual Fieldbus Simulator can not be used as a real TwinCAT replacement and is not designed to use in productional tasks.