YOKOGAWA SCP451-11 CPU
1. Introduction
The Yokogawa SCP451-11 is a high-performance Processor Module (CPU) designed for use in the Field Control Stations (FCS) of the CENTUM VP Distributed Control System.
It serves as the “brain” of the AFV30 or AFV40 control units.
The SCP451 handles complex control logic calculations, manages I/O communication, and coordinates data exchange with the Human Interface Station (HIS) via the Vnet/IP network.
The “-11” suffix specifically denotes its revision level, optimized for high-speed processing and enhanced memory capacity to support large-scale plant operations.
2. Technical Parameter Table
| Feature | Specification |
| Model | SCP451-11 |
| Processor Type | High-speed industrial microprocessor |
| Main Memory | Error-Correcting Code (ECC) RAM |
| Control Cycle | 10 ms to 1 s (selectable) |
| Max. I/O Capacity | Supports up to 8 nodes / 80 modules (depending on rack) |
| Control Loops | Typically supports 100+ PID loops depending on complexity |
| Current Consumption | 1.5 A at 5 V DC (internal) |
| Redundancy | Dual-redundant support (requires two modules) |
| Weight | Approx. 0.45 kg |
| Operating Temp | 0 to 55°C |
| Style Code | S1 (Standard Style) |
3. Product Advantages and Features
Dual Redundancy: Two SCP451 modules can be used in a “dual-redundant” configuration. If the active processor fails, the standby processor takes over in less than a single control cycle (bumpless transfer).
Vnet/IP Integration: Natively designed to communicate over the 1 Gbps Vnet/IP control network when paired with a VI451 interface module.
Data Integrity: Utilizes ECC (Error-Correcting Code) memory to prevent system crashes caused by soft memory errors, which is critical for continuous 24/7 operation.
Online Download: Supports “Online Change” capabilities, allowing engineers to update control logic without stopping the processor or the plant process.
Self-Diagnostics: Continuous background hardware checks monitor CPU health, memory parity, and temperature.
SCP451-11
4. Application Cases
Petrochemical Refineries: Managing large-scale distillation units and catalytic crackers where high-speed, redundant control is mandatory.
Power Plants: Controlling boiler and turbine parameters where high reliability and fast response times are required for safety.
Pharmaceutical Manufacturing: Used in batch processes that require precise timing and high-resolution data logging for regulatory compliance.
Global Export Machinery: Ideal for large-scale OEMs who integrate DCS control into high-complexity skid units.
| Bently | 3500/44M |
| BENTLY | 1900/65-00-01-03-01-01 |
| BENTLY | 3500/22M |
| BENTLY | 3500/22M 288055-01 |
| BENTLY | 3500/92 136180-01 |
| BENTLY | 131151-01 |
| BENTLY | 3500/22M 288055-01 |
| BENTLY | 128229-01 |
| BENTLY | 3500/22-01-01-00 |
| BENTLY | 136719-01 |
| BENTLY | 9200-01-01-10-00 |
| BENTLY | 3500/05 |
5. Related Models & Same Series
The SCP451 is the centerpiece of the AFV series controller architecture.
Other Models in the Same Series
SCP401: An earlier processor version used in the original AFV10 series.
SCP461: A related processor model used in different bus configurations or specialized bridge units.
SCP451-10: The previous style revision of the same module.
Related System Components
AFV30S / AFV30D: The Field Control Units (Single or Duplex) that house the SCP451.
VI451: The Vnet/IP interface module used alongside the processor.
PW441: The power supply module that provides DC power to the SCP451.