ABB PM891 Processor Unit – High-Performance CPU with Redundancy and CEX-Bus Expansion

The ABB PM891 Processor Unit is a high-performance, monolithic automation controller designed for reliable operation in demanding industrial environments. Integrated with a power supply, CPU boards, and unit termination, the PM891 supports mission-critical applications where uptime and scalability are essential.

Equipped with a powerful microprocessor, RAM memory, real-time clock, LED indicators, and Secure Digital (SD) interface, the PM891 is built for modern automation tasks. Its two RJ45 Ethernet ports (CN1 and CN2) allow seamless connection to control networks, while the isolated serial port (COM4) supports secure configuration.

This processor also supports CPU redundancy, enabling continuous operation even during component failure. The CEX-Bus allows communication port expansion with support for redundant communication interfaces for increased system availability.

Key Features:

• Integrated power supply and processor in a single unit

• Dual Ethernet ports for network redundancy

• Isolated RJ45 serial port (COM4) for configuration

• Built-in CEX-Bus for communication interface expansion

• Supports CPU and interface redundancy for high availability

• Optical Modulebus supports up to seven clusters of S800 I/O units

• Unique Ethernet address for hardware identity

The BC810 Interconnection Unit enhances availability on the CEX-Bus by dividing it into independent segments, ensuring fault isolation and maximum system uptime.

Ideal for industrial control systems, the PM891 delivers reliable, scalable, and redundant processing power to meet the needs of modern automation.