Yokogawa Duplicated Field Control Unit (FCU) | AFV10D-S41251

Product Overview

The Yokogawa AFV10D-S41251 serves as the primary control station for the CENTUM VP Distributed Control System (DCS). As a Duplicated (Duplexed) Field Control Unit, it is engineered for critical process environments where continuous operation is mandatory. This unit houses the redundant processor modules that execute regulatory control, complex sequence logic, and real-time data calculations. The "D" prefix signifies its redundant architecture; if the primary controller encounters a hardware fault, the secondary unit assumes control instantaneously, ensuring zero process interruption.

Condition: 100% Brand New and Original Factory Sealed.

Part Number Breakdown: AFV10D-S41251

Yokogawa utilizes a specific suffix code to define the power, mounting, and networking specifications of the FCU:

• AFV10D: Duplicated Field Control Unit (for Vnet/IP and FIO).

• -S: Standard type.

• 4: Dual-redundant 100-120 V AC Power Supply.

• 1: 19-inch Rack-mount type.

• 2: Vnet/IP Interface (Redundant).

• 5: Enhanced hardware revision with G3 corrosive resistance protection.

• 1: Basic hardware version for optimized processor stability.

Technical Specifications

The AFV10D-S41251 provides high-speed processing and environmental hardening for modern industrial automation.

• Processor Type: High-performance RISC processor.

• Control Network: Vnet/IP (1 Gbps Redundant Ethernet).

• I/O Bus: FIO (Field Input/Output) bus interface.

• Memory Protection: Battery-backed RAM for database retention.

• Environmental Protection: ISA Standard S71.04 Class G3 (Corrosive Resistance).

• Power Supply: 100-120 V AC, 50/60 Hz (Dual-redundant).

• Mounting: Standard 19-inch rack-mount.

Engineering Advantages

• Mission-Critical Redundancy: The AFV10D-S41251 is designed for high-availability "Hot Standby" operation. Both CPU modules synchronize data in real-time. In the event of a failure on the active processor, the backup takes over in less than one scan cycle, preventing any "bumps" in the control output.

• G3-Rated Environmental Protection: The "5" in the suffix indicates that this unit is treated with a conformal coating to meet ISA G3 standards. This protects the internal circuitry from corrosive gases like $H_{2}S$ and $SO_{2}$, making it ideal for refineries, chemical plants, and wastewater facilities.

• High-Speed Vnet/IP Connectivity: Utilizing a 1 Gbps Vnet/IP network, this controller communicates massive amounts of data to the HMI and other control stations with minimal latency. This is critical for large-scale plants with thousands of active control loops.

• Seamless FIO System Integration: This FCU acts as the master for Yokogawa’s FIO (Field I/O) modules (e.g., ADV151, ADV551). The local bus architecture ensures rapid data refresh rates between field sensors and the controller's logic engine.

• Online Maintenance & Hot-Swapping: Redundant components, including power supply units and communication cards, can be replaced while the plant remains under active control. This significantly improves the Mean Time to Repair (MTTR) and reduces the risk of human error during maintenance.

FAQs

• What is the main difference between AFV10D and AFV10S?

  The AFV10D is the Duplexed (redundant) version containing two CPU modules, while the AFV10S is a Single (non-redundant) version. For any critical safety or production loop, the AFV10D is the industry standard.

• Does this unit include the CPU cards (CP461)?

  The AFV10D-S41251 specifies the chassis, power, and environmental rating. While it is designed to hold the CPU modules, the specific modules (typically CP461) are often listed as separate components in a complete system order.

• Can this unit be used in a 220V AC environment?

  No. This specific model (suffix "-4") is rated for 100-120 V AC. For 220-240 V AC power environments, you would require the suffix "-2" version of the AFV10D.

• How often should the backup battery be replaced?

  The lithium battery (Part No. S9185FA) preserves the control database during power loss. We recommend a proactive replacement every 3 to 5 years during a scheduled plant turnaround.