The Mid-End Control Core serves as the main CPU module within the ABB AC500 series PLC platform, offering an optimal balance between processing performance, scalability, and system integration.
It is designed to handle a wide range of automation and control tasks, including logic control, PID process regulation, sequential control, and high-speed counting, making it suitable for medium-scale automation projects such as production line coordination and complex process monitoring.
With support for multitask parallel execution and real-time data processing, the module ensures fast and deterministic control response in dynamic industrial environments.

2. Functional Characteristics

Flexible Programming and Integration

Compatible with ABB Automation Builder software, following the IEC 61131-3 programming standard.

Supports multiple programming languages — Ladder Diagram (LD), Function Block Diagram (FBD), Structured Text (ST) — allowing engineers to implement control logic efficiently.

Includes a library of predefined function blocks (e.g., motion control, closed-loop regulation, timer and counter modules), simplifying complex control development.

Fully compatible with all AC500 series I/O modules (digital, analog, and special function types) and communication modules, providing seamless system scalability and functional expansion.

Efficient Communication Capability

Built-in 10/100 Mbps Ethernet and RS-485 communication interfaces.

Supports multiple industrial communication protocols, including Modbus TCP/IP, Profinet, and EtherNet/IP.

Enables high-speed data exchange with HMI, SCADA, MES, and other PLCs, supporting distributed architectures and Industrial Internet of Things (IIoT) connectivity.

Ideal for establishing interconnected control networks in small to medium industrial automation systems.

3. Technical Parameters

Category	Specification
Processor	32-bit industrial-grade CPU
Program Memory	2 MB (expandable)
Data Memory	1 MB
Instruction Execution Time	Within microseconds (depending on logic complexity)
Communication Ports	Ethernet (10/100 Mbps), RS-485
Supported Protocols	Modbus TCP/IP, Profinet, EtherNet/IP
I/O Expansion	Supports multiple I/O racks via AC500 backplane bus; up to several thousand I/O points (depending on configuration)
Reliability Features	Watchdog timer, power-fail detection, online program modification, firmware upgrade support
Power Supply	24 V DC (19.2–30 V DC)
Operating Temperature	-25 °C to +60 °C
EMC and Vibration Resistance	Complies with industrial standards
Installation	Mounted on AC500 standard rail/rack
Typical Applications	Medium-sized machines, production lines, water treatment systems, and infrastructure automation

4. Reliability and Environmental Adaptability

Incorporates self-diagnostic mechanisms such as a watchdog timer and power failure detection, ensuring system stability and fault tolerance.

Supports online program editing and firmware updates, minimizing system downtime during maintenance or modification.

Rugged design with anti-vibration and electromagnetic interference protection, ensuring reliable performance under harsh industrial conditions.

Wide operating temperature range (-25 °C to +60 °C) allows deployment in diverse environments such as manufacturing plants, utilities, and process control sites.

5. Key Advantages

Balanced performance for medium-scale automation systems.

Modular and scalable architecture supporting system growth.

Rich communication options for networked and distributed control.

Proven industrial reliability with ABB engineering quality.

Fully compatible with the AC500 PLC ecosystem, enabling flexible system design and long-term maintainability.