Overview of ABB AC 800M Controller

The ABB AC 800M for Advant Master DCS is a modular process controller designed to deliver flexible, scalable, and high-performance control solutions for industrial automation systems. It supports a wide range of CPU modules—from cost-efficient options to high-performance, fully redundant models—allowing system engineers to select configurations that best fit their control requirements.

Modular Architecture for Flexible System Design

AC 800M adopts a rail-mounted modular design that includes CPU units, communication modules, power supplies, and accessories. This modularity enables seamless system expansion and easy integration with diverse industrial applications. The platform’s open architecture supports standard industrial communication protocols, making it adaptable to both new and legacy control systems.

CPU and Network Redundancy for Reliable Operation

Redundancy is a core feature of the AC 800M design. Each system can be configured with dual CPU modules—one active and one standby—to ensure uninterrupted control performance. In case of a CPU failure, the secondary processor automatically takes over without process disruption.
Network redundancy is achieved through ABB’s Redundant Network Routing Protocol (RNRP), which provides fast fault detection and instant switch-over between dual Ethernet networks. This ensures continuous data communication and maximum system availability, even during network disturbances.

Advanced Control and Reusable Libraries

The AC 800M platform supports a wide spectrum of control functions, including binary, sequential, and closed-loop control. Engineers can implement advanced algorithms such as auto-tuning, adaptive PID, and fuzzy control for complex industrial processes.
ABB’s reusable function block libraries, including predefined motor and valve objects, accelerate project engineering while maintaining consistency. Users can also create custom function blocks to safeguard proprietary control logic and intellectual property.

Communication Options and Integration with Advant Master

AC 800M offers multiple communication interfaces to connect with both Advant Master and other control environments. Its flexible communication modules enable system expansion and integration with various industrial networks:

• CI856 – Connects to Advant Master S100 I/O racks, supporting up to five racks per module.

• CI855 – Facilitates MasterBus 300 communication with Advant Controller 450 and MasterPiece 200 systems.

• CI869 – Enables Advant Fieldbus 100 data exchange with Advant Controller 450.

• CI871 – Supports PROFINET communication for modern S800 I/O integration.

• CI854B – Provides PROFIBUS DP connectivity for S800 I/O when migrating from Advant Fieldbus 100.

• TB840 – Manages ModuleBus communication with S800 I/O modules.

• CI853/CI867 – Offer Modbus and Modbus/TCP interfaces for Ethernet-based data exchange.

These communication options make AC 800M ideal for hybrid environments where legacy Advant systems coexist with newer Ethernet-based infrastructures.

Application Benefits and Engineering Efficiency

The AC 800M’s scalability and communication flexibility simplify both new project designs and system modernization efforts. For plants transitioning from legacy Advant controllers to contemporary DCS architectures, the AC 800M offers smooth migration with minimal re-engineering.
Its compatibility with multiple I/O systems allows users to reuse existing field assets, reducing total project costs. Furthermore, integrated redundancy and diagnostics enhance reliability, making it a preferred choice for mission-critical industries such as oil and gas, power generation, and chemicals.

Author Commentary: The Role of Modular DCS in Future Automation

The ABB AC 800M exemplifies the industry shift toward modular, software-driven control systems. In the era of Industry 4.0, DCS platforms must not only handle process control but also integrate seamlessly with enterprise-level data and analytics. ABB’s approach—with open connectivity, scalable hardware, and robust redundancy—illustrates how traditional process control systems are evolving into flexible automation ecosystems.
For automation engineers, this means easier system maintenance, faster deployment, and improved interoperability with both PLC-based and cloud-connected solutions.

Typical Applications and Use Cases

• Process automation in power generation and refining

• Integration of legacy Advant Master systems with new DCS platforms

• High-availability control environments requiring redundancy

• Multi-network systems using PROFIBUS, PROFINET, or Modbus communication

• Complex process plants requiring advanced PID or adaptive control