ABB PM 802F AC800F Central Processing Unit Base Unit

The ABB PM 802F 3BDH000002R1, also cataloged as the PM802F Central Processing Unit Base Unit, operates as a dedicated hardware component for process control execution and logic processing within ABB AC800F DCS platforms. Equipped with a Super Scalar RISC microprocessor delivering performance up to 150 MIPS, this unit directly manages data transfers between internal memory registers and connected local digital and analog I/O modules across the system backplane bus.

Hardware Specifications

Firmware Flash Compatibility and Memory Bus Architecture

The PM 802F controller unit utilizes a 32-bit Flash-EPROM architecture combined with 4 MB of battery-buffered Static RAM featuring built-in error detection and correction routines. Firmware images and user control logic stored within the 4 MB Flash-EPROM execute directly on the 150 MIPS Super Scalar RISC processor, maintaining deterministic cycle execution over the local system bus. System configuration settings and hardware identification parameters are safely written to the integrated 16 Kbit serial EEPROM, preserving system state during total backplane power cycles.

Frequently Asked Questions

Q: How does the PM 802F handle memory integrity during unexpected power loss?

A: The PM 802F uses battery-buffered static RAM combined with integrated hardware error detection and correction (EDAC) to retain process variables and prevent memory corruption during backplane power disruptions.

Q: What processor architecture executes control tasks in the PM802F module?

A: Execution is driven by an onboard Super Scalar RISC microprocessor operating at throughput speeds up to 150 MIPS, supported by 16 KB of internal CPU cache memory.

Q: Can the PM802F communicate directly with external field devices without intermediate expansion units?

A: The PM 802F serves as the primary processing unit and routes field signals via compatible digital and analog input/output interface cards mounted on the system backplane.

Field Installation Guidelines

1. Power down the AC800F rack chassis before inserting or removing the PM802F base module to avoid backplane voltage spikes.
2. Ensure the module card edges align correctly with the chassis guide rails before applying firm horizontal pressure to seat the rear interface connectors.
3. Secure all mechanical locking screws to a recommended torque of 0.5 Nm to guarantee solid chassis grounding and structural stability.
4. Maintain a minimum clear distance of 50 mm above and below the module rack assembly to allow unobstructed vertical airflow for thermal dissipation.
5. Connect cabinet shielding and ground straps directly to the main rack ground point using low-impedance copper grounding wire.