Product Core Brief
- Model: CP451-51
- Brand: Yokogawa
- Series: CENTUM VP / CS 3000
- Core Function: Field Control Station processor for regulatory and sequence control
- Product Type: Processor Module (CPU Card)
- Key Specs: AFV300/AFV400 compatible | ISA G3 coating | 1:1 redundancy
- Condition: New Surplus / Refurbished options available
Product Introduction
The Yokogawa CP451-51 is the Field Control Station processor for the CENTUM VP distributed control system. It executes regulatory control loops, sequence logic, and communication management for AFV300 and AFV400 controller nodes.
The “-51” suffix identifies this as the standard hardware type with ISA Standard G3 conformal coating . That coating protects the PCB against sulfurous, chlorine-based, and other corrosive airborne contaminants—critical for pulp and paper mills, wastewater plants, and chemical facilities where unprotected electronics fail prematurely. This module is a drop-in replacement for the older CP451-11, but verify your Vnet/IP infrastructure and firmware revision before committing.
Frequently Asked Questions
Q: Is this a PLC module or a DCS processor?
A: It is a DCS processor, not a PLC slice. Some Chinese listings describe it as an “analog input/output module” for PLC systems . That is fabricated. The CP451-51 is the central computing engine for a Yokogawa CENTUM VP Field Control Station. It does not plug into a generic PLC rack.
Q: What does the “-51” suffix actually mean?
A: Per Yokogawa’s model selection table: “-5” is standard type with no explosion protection, and “1” adds the ISA Standard G3 option . So “-51” = standard hardware + G3 conformal coating. If you need explosion protection, that is a different suffix. Do not assume all CP451 variants are interchangeable without checking the full suffix code.
Q: Can I replace a CP451-11 with this CP451-51 directly?
A: Physically, yes—it is designed as the successor . But two conditions apply. First, your system must run the correct firmware revision for the CP451-51. Second, if you are upgrading from an older Vnet-based system, you may need a software revision update and database conversion in System View . Do not swap the card without confirming the engineering station can recognize it.
Q: Will I lose the control program during replacement?
A: The application logic lives in the engineering database and is loaded to the processor at startup. But the processor maintains program memory during power-down via a lithium backup battery . Before pulling a failed unit, attempt a database upload if the processor still responds. If it is dead, you will need a recent backup from the engineering station.
