System overview

TwinCAT 3 PLC realises one or more PLCs with the international standard IEC 61131-3 3rd edition on one CPU. All programming languages described in the standard can be used for programming. The blocks of the type PROGRAM can be linked with real-time tasks. Various convenient debugging options facilitate fault-finding and commissioning. Program modifications can be carried out at any times and in any size online, i.e. when the PLC is running. All variables are available symbolically by ADS and can be read and written in appropriate clients.


TwinCAT 3 PLC provides you with versatile and comfortable engineering functions for your development work:


See also in this online help:

Project configuration through wizards

Creating and configuring a project

Interface customization

Customize interface

Generation of professional control programs according to IEC 61131-3 with many standard features

Programming a PLC project

Convenient programming with mouse and keyboard in all IEC 61131-3 languages

Corresponding editors for FBD, LD, IL, ST, SFC, plus the variants CFC and Extended CFC

Programming languages and their editors

Input support for input and configuration of a wide range of data

Using the input wizard

Support of object-oriented programming

Genuine object-oriented programming according to 61131-3 third edition, in all IEC 61131-3 languages possible without additional tools

Inheritance of program blocks to similar program parts to reduce development time and errors

Object-oriented programming is not a must: functional or object-oriented programming can be used and mixed as required

Object-oriented programming

Comprehensive project comparison, also for graphic editors

Compare projects

Library concept for convenient reuse of program code

Using libraries

Debugging and online features to optimize program code and speed up testing and commissioning

Testing and debugging

Integrated compilers for various CPU platforms

Project properties – Category Compile

Security properties for protecting the source code and operating the controller

Protecting and saving a project

Encrypting a PLC project

Using Help

Each help component consists of a conceptual part and a reference part. The conceptual part provides detailed explanations of all the topics that are relevant for creating, managing and executing a TwinCAT 3 PLC project. The descriptions are supplemented by step-by-step instructions for achieving the desired result. The reference parts are complete reference works for the user interface and programming of TwinCAT 3 PLC. See also the "TC3 User Interface" documentation.