AC 800F Base Unit CPU Overview

The 3BDH000530R1 (PM 803F) is a central base unit within ABB’s AC 800F control system, equipped with a 16 MB battery-buffered RAM architecture. It serves as the core processing unit responsible for executing control logic, managing system communication, and coordinating distributed automation modules.

The PM 803F is designed as a modular CPU platform, allowing integration of various functional modules depending on application requirements. It is widely used in process automation systems where deterministic control performance and system scalability are required.

System Architecture & Processor Design

The PM 803F base unit consists of a CPU main board housed within a modular chassis and supports flexible system expansion:

• Core Processing Unit: Central CPU module for AC 800F distributed control system operations.
• Memory Architecture: 16 MB battery-buffered RAM ensures data retention during power interruption.
• Modular Design: Supports additional functional modules depending on system configuration.
• Software Dependency: No operating system pre-installed; OS must be loaded during software setup.
• Hardware Interface: Equipped with RW 855F contact ledge for system-level connectivity.

Electrical & Mechanical Data

Operational & System Considerations

Does the PM 803F include an operating system?

No. The unit is delivered without a pre-installed operating system. The OS must be installed during system commissioning using ABB software tools.

What is the performance difference compared to PM 802F?

The PM 803F has approximately 5–10% lower performance compared to the PM 802F, which should be considered when designing high-load control applications.

Is the PM 803F suitable for modern system upgrades?

It is still used in existing AC 800F installations, but for new projects ABB typically recommends newer AC 800M-based architectures for higher processing performance and long-term support.

Installation & Commissioning Notes

Software Compatibility:
Ensure software version V7.1 SP2a or higher is used during installation. Lower versions may not support full hardware functionality.

Contact Ledge Handling:
The RW 855F contact ledge must be properly seated during installation to ensure stable communication between CPU and backplane modules.

Power Stability:
Since memory is battery-buffered, verify battery condition during maintenance cycles to prevent data loss during unexpected power failure.

System Expansion:
Additional modules can be integrated into the AC 800F rack, but system load and communication timing should be evaluated during design phase.