As the central processing unit (CPU) of the ABB AC500 PLC, this module is responsible for executing user-defined control programs, processing digital and analog input/output signals, and coordinating communication with I/O modules, communication modules, and other peripheral devices.
It performs essential automation control functions such as logic operations, timing, counting, and closed-loop regulation, enabling precise and reliable control of industrial equipment and production processes.

Programming and Scalability:
Supports configuration and programming via ABB Automation Builder software, fully compliant with the IEC 61131-3 standard. Compatible programming languages include Ladder Diagram (LD), Function Block Diagram (FBD), and Structured Text (ST), allowing engineers to develop and customize control logic efficiently.
System scalability is achieved through AC500 series expansion I/O modules (digital, analog, and special-function types) connected via the backplane bus, enabling flexible adaptation to control applications of varying scale and complexity.

Communication Capabilities:
The CPU integrates standard industrial communication interfaces such as RS-485 and Ethernet, supporting widely used industrial protocols including Modbus, PROFINET, and EtherNet/IP.
This ensures seamless data exchange with HMI, SCADA systems, supervisory computers, or other PLCs, supporting the creation of distributed and networked automation systems.

2. Technical Parameters and Specifications

Parameter	Description
Processor and Memory	Equipped with a high-performance microprocessor, integrating program memory (approx. 800 KB) and data memory (approx. 512 KB) to meet the storage and real-time processing needs of small to medium-sized automation systems.
I/O Processing Capacity	Supports a large number of I/O points depending on the selected expansion modules — typically expandable to hundreds of I/O channels, suitable for diverse industrial control applications.
Communication Interfaces	RS-485, Ethernet; supports Modbus, PROFINET, and EtherNet/IP protocols for system integration and network communication.
Programming Environment	ABB Automation Builder, compliant with IEC 61131-3 (LD, FBD, ST).
Power Supply	24 V DC, industrial-grade.
Installation Method	Mounted on the AC500 series DIN rail; modular design simplifies replacement, expansion, and maintenance.
Operating Temperature Range	–25°C to +60°C, ensuring reliable operation in harsh industrial environments.
Environmental Resistance	Designed with anti-vibration and electromagnetic interference (EMI) protection, suitable for use in demanding industrial conditions.