The Yokogawa AFS10S Field Control Unit (FCU) is a single-controller processor designed for CENTUM CS 3000 and early CENTUM VP Distributed Control Systems using the Remote I/O (RIO) architecture. As the processor of a Field Control Station (FCS), the AFS10S executes process control applications, communicates with Remote I/O nodes, and exchanges operational data with Human Interface Stations (HIS). The controller features a 16 MB main memory with battery-backed retention and is intended for 19-inch rack installation. Proper installation, wiring, grounding, and commissioning are essential to ensure reliable long-term operation.

Contents

• 1. AFS10S Field Control Unit Overview
• 2. Technical Features
• 3. Typical Industrial Applications
• 4. Installation Planning
• 5. Hardware Inspection
• 6. Installation Environment
• 7. Rack Mounting Procedure
• 8. Power Supply Connections
• 9. RIO Communication Connections
• 10. Grounding Requirements
• 11. Commissioning Procedure
• 12. Functional Testing
• 13. Preventive Maintenance
• 14. Practical Installation Case
• 15. Frequently Asked Questions

AFS10S Field Control Unit Overview

The AFS10S is a non-redundant Field Control Unit that serves as the processing core of a CENTUM Field Control Station. It communicates with Remote I/O nodes over the RIO bus while executing regulatory, sequence, and logic control functions. The controller is intended for applications where processor redundancy is not required. It is equipped with battery-backed memory capable of retaining application data during temporary power interruptions.

Technical Features

• Single-controller architecture
• 16 MB main memory
• Battery-backed memory retention
• RIO communication interface
• 19-inch rack-mount design
• FCU status contact output
• Supports up to eight RIO nodes

Typical Industrial Applications

• Oil and gas production
• Chemical processing plants
• Petrochemical facilities
• Power generation
• Water treatment systems
• General process automation

Installation Planning

• Review system engineering drawings
• Verify rack dimensions
• Confirm power supply availability
• Review RIO network layout
• Prepare controller configuration files

Hardware Inspection

• Verify model identification
• Inspect communication interfaces
• Check mounting hardware
• Inspect terminal blocks
• Verify controller condition before installation

Installation Environment

• Maintain adequate ventilation
• Avoid excessive humidity
• Protect against vibration
• Prevent conductive dust accumulation
• Maintain specified ambient temperature

Rack Mounting Procedure

1. Disconnect cabinet power.
2. Install the controller into the designated rack position.
3. Secure mounting screws.
4. Verify proper module seating.
5. Inspect cable routing.
6. Confirm connector engagement.

Power Supply Connections

• Connect the specified power supply.
• Verify input voltage.
• Inspect protective devices.
• Confirm wiring integrity.
• Verify power indicators after startup.

RIO Communication Connections

• Connect the Remote I/O bus.
• Verify communication cable integrity.
• Check node addressing.
• Inspect connectors.
• Label communication cables.

Grounding Requirements

• Connect protective earth.
• Verify cabinet grounding.
• Maintain low grounding resistance.
• Avoid ground loops.
• Inspect grounding continuity.

Commissioning Procedure

VERIFY INSTALLATION
CONNECT POWER
VERIFY GROUNDING
CONNECT RIO NETWORK
POWER UP CONTROLLER
DOWNLOAD APPLICATION
VERIFY COMMUNICATION
START PROCESS OPERATION

Functional Testing

• Verify successful startup.
• Confirm RIO communication.
• Validate controller diagnostics.
• Verify application execution.
• Confirm stable process control.

Preventive Maintenance

• Inspect communication cables regularly.
• Review controller diagnostics.
• Replace backup battery according to maintenance schedules.
• Maintain configuration backups.
• Inspect cabinet cooling systems.

Practical Installation Case

During commissioning of a chemical processing unit, engineers observed that several Remote I/O nodes remained offline after controller startup.

Inspection revealed an incorrectly addressed RIO node that prevented communication with the controller.

After correcting the node address:

• All RIO stations communicated normally.
• Application download completed successfully.
• Controller diagnostics reported normal status.
• The process entered stable operation.

Frequently Asked Questions

What is the AFS10S used for?

The AFS10S is a single Field Control Unit that executes process control applications and communicates with Remote I/O equipment in CENTUM control systems.

Does the AFS10S support processor redundancy?

No. The AFS10S is a single-controller model. Applications requiring controller redundancy use the AFS10D duplexed version.

How much memory is available?

The controller provides 16 MB of main memory with battery backup capable of preserving memory contents during temporary power interruptions.

Summary: Proper installation of the Yokogawa AFS10S Field Control Unit requires secure rack mounting, reliable power wiring, correct RIO communication connections, effective grounding, and comprehensive commissioning. Following these procedures ensures dependable controller performance and long-term process control reliability.