#plc software

When it comes to PLC programming software, Codesys is certainly well-known, but there is more to learning industrial automation than just this one! The following two open source PLC software can help you start your automation journey at a low cost:

Beremiz: Flexible & Powerful, Geared Towards Complex Automation & Integration

Core Positioning: A complete, IEC 61131-3 standards-compliant Integrated Development Environment (IDE) for machine automation, emphasizing flexibility and protocol support.

Key Components:

IDE (Beremiz.py): Runs on the user's computer, supporting all five IEC 61131-3 programming languages. Its unique feature is using the MatIEC compiler to translate programs into C code, which is then compiled into machine code for the target platform using the standard GCC toolchain, enabling true cross-hardware-platform deployment.

Runtime (Beremiz_service.py): Implemented in Python or C, responsible for executing the compiled program and handling I/O communication. Supports Linux, Windows, and macOS.

Standout Advantages:

Robust Industrial Protocol Integration: Natively supports key industrial bus/communication protocols like Modbus, EtherCAT, CANopen, OPC UA, facilitating integration with various devices and upper-level systems.

Built-in HMI Development Tool (SVGUI): Allows designing and building Human-Machine Interfaces (HMI) directly within the IDE using SVG vector graphics, simplifying the visualization development process.

Deep Hardware Adaptation Potential: The C code compilation characteristic enables efficient operation on resource-constrained embedded platforms (e.g., ARM Cortex-M microcontrollers) and also supports more powerful systems.

Ideal Use Cases: Machine automation, systems requiring complex control logic, projects needing multi-protocol integration, teaching and research (especially combining compiler principles with real-time control), development of customized industrial controllers.

Official Website: https://beremiz.org/

OpenPLC: Lightweight & Versatile, King of Hardware Compatibility

Core Positioning: The first fully open-source (software + hardware reference) and IEC 61131-3 standards-compliant full-featured PLC solution.

Key Components:

Runtime: The core execution engine, extremely resource-efficient, perfectly suited for embedded devices and IoT edge nodes.

Editor: Intuitive and easy to use, supports all five IEC languages: Ladder Diagram (LD), Function Block Diagram (FBD), Instruction List (IL), Structured Text (ST), and Sequential Function Chart 

(SFC).HMI/SCADA Integration: Seamlessly integrates by default with the powerful open-source SCADA system ScadaBR (via Modbus/TCP communication), enabling convenient web-based monitoring.

Standout Advantages:

Extremely Wide Hardware Support: Ranges from entry-level Arduino (Uno, Nano, Mega), ESP8266/ESP32, to Raspberry Pi (RPi 2/3/4), industrial-grade platforms like Controllino, UniPi, Neuron PLC, and even Windows/Linux soft PLCs – covering almost everything!

Ideal for Security Research: Due to its open-source nature and industrial protocol implementations, it is widely used for learning, testing, and attack/defense drills in Industrial Control System (ICS) cybersecurity.

Ideal Use Cases: Home automation, small SCADA systems, low-cost industrial control prototypes, IoT edge control, ICS security experimentation platforms.

Official Website: https://autonomylogic.com/

EtherCAT is an open, real-time, and deterministic Ethernet fieldbus standard widely regarded as one of the best industrial networks to date. Automation equipment manufacturers can use EtherCAT on their own device implementations to improve performance and flexibility, while end users and automation system designers can implement their own EtherCAT-compliant devices. An EtherCAT network works more efficiently frame is sent from the master and when the first slave device receives the frame, it instantly extracts the data with its address and writes any response data. This means that the frame effectively passes through all the slaves and then returns to the master.