Yokogawa FA-M3 F3LC21-1N LC21-1N Multi-Link Communication Module

Technical Dossier

Product Details And Specifications

Yokogawa FA-M3 Series Technical Notes

The Yokogawa FA-M3 (also marketed under the STARDOM and F3-series designations) is a modular programmable controller platform with a documented installation base across global heavy industry sectors including petrochemical complexes, nuclear power auxiliary systems, offshore oil & gas platforms, and continuous-process refineries. Its backplane-based architecture supports deterministic scan cycles and high-density I/O expansion, making it a reference platform for safety-instrumented and process-control applications where long operational lifecycles — often exceeding 20 years — are standard procurement requirements. The F3LC21-1N is a Multi-Link communication module within this platform, providing inter-controller network connectivity across FA-M3 rack systems.

The Evolution of FA-M3 Architecture

The FA-M3 platform was introduced by Yokogawa Electric Corporation as a successor to its earlier FA-500 and FA-700 controller families. The architecture evolved through three identifiable generations. The first generation established the F3-series module numbering convention and the multi-slot base unit design. The second generation introduced high-speed CPU modules (F3SP28, F3SP38) with expanded memory and Ethernet-capable communication cards. The third generation, represented by modules such as the F3SP71 and F3SP76, added IEC 61131-3 programming compliance and dual-redundancy support.

The F3LC21-1N belongs to the Link Communication category, enabling peer-to-peer data sharing between FA-M3 CPUs over a dedicated multi-link network — a topology distinct from the standard Ethernet or RS-232C interfaces found on other F3-series cards. Compatibility is constrained to specific CPU generations; integration with third-party controllers requires gateway hardware. As the FA-M3 platform has entered its mature/end-of-active-production phase for several module types, sourcing certified replacement units has become the primary maintenance strategy for installed-base operators.

FA-M3 Full Catalog & Functionalities (SKU List)

CPU Modules

• F3SP22-0S: Standard CPU, 30K-step ladder, RS-232C port, basic I/O control.
• F3SP28-3S: Mid-range CPU, 60K-step, dual-port Ethernet, expanded data registers.
• F3SP38-6S: High-speed CPU, 120K-step, multi-task execution, large memory map.
• F3SP53-4H: High-performance CPU with motion control integration capability.
• F3SP58-6S: Enhanced CPU, 250K-step, supports function block programming.
• F3SP71-4N: IEC 61131-3 compliant CPU, dual Ethernet, redundancy-ready architecture.
• F3SP76-7N: Top-tier FA-M3 CPU, 500K-step, SFC/FBD/ST language support, hot-standby redundancy.

Communication & Link Modules

• F3LC21-1N (LC21-1N): Multi-Link communication module; inter-CPU data sharing over dedicated link network.
• F3LC11-1N: Single-channel link module for point-to-point FA-M3 controller interconnection.
• F3LE01-5T: 10BASE-T Ethernet interface module, Modbus TCP and FINS protocol support.
• F3LE11-1T: 100BASE-TX Ethernet module, high-throughput data acquisition interface.
• F3LP02-0N: RS-232C/RS-422 serial communication module, multi-protocol configurable.

Digital I/O Modules

• F3XD32-3H: 32-channel 24VDC digital input module, high-density rack mounting.
• F3YD32-3H: 32-channel transistor digital output module, 0.1A per point rating.
• F3XD16-3N: 16-channel DC input module, standard logic-level signal acquisition.
• F3YR16-0N: 16-channel relay output module, 2A contact rating, isolated commons.

Analog I/O Modules

• F3AD04-1N: 4-channel analog input, 4–20mA / 0–10V selectable, 12-bit resolution.
• F3AD08-1N: 8-channel analog input module, process signal conditioning integrated.
• F3DA04-1N: 4-channel analog output, 4–20mA, suitable for valve positioner control loops.

Power Supply Modules

• F3PU20-0S: 24VDC input power supply module, standard FA-M3 base unit power source.
• F3PU30-0S: High-capacity power supply for large I/O configurations, overcurrent protected.