Yokogawa ALF111-S51 Fieldbus Communication Module

The Yokogawa ALF111-S51 is a FOUNDATION Fieldbus (FF-H1) communication module used in Yokogawa CENTUM VP and CENTUM CS 3000 Distributed Control Systems (DCS).

It is designed to enable high-speed, deterministic field communication between control systems and field devices, supporting reliable integration of intelligent instruments in process automation environments. With robust industrial-grade architecture, the ALF111-S51 ensures stable data exchange, reduced wiring complexity, and improved system diagnostics.

This module is widely used in oil & gas, petrochemical, power generation, and chemical industries, where advanced fieldbus communication is required for smart instrumentation networks.

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Technical Specifications

Parameter	Specification
Brand	Yokogawa
Model	ALF111-S51
Product Type	FOUNDATION Fieldbus Communication Module
Fieldbus Type	FF-H1 (31.25 kbps)
Number of Ports	4 ports
Supported Devices	Fieldbus instruments (transmitters, valves, analyzers)
System Compatibility	CENTUM VP / CS 3000
Communication Function	Control + monitoring + diagnostics
Redundancy Support	Yes (system dependent configuration)
Installation Type	Rack-mounted DCS module
Operating Temperature	-20°C to +70°C

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Physical Characteristics

Item	Specification
Dimensions (W × H × D)	Approx. 115 × 130 × 32 mm
Weight	Approx. 0.3 – 0.6 kg
Mounting	Vnet/IP or FIO rack installation
Cooling	Natural convection (no fan required)
Build	Industrial-grade electronic module

Compact design allows high-density installation inside Yokogawa control cabinets.

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Recommended Related Models

• Yokogawa ALF111-S50 – standard FF communication module version
• Yokogawa ALP121 – PROFIBUS-DP communication module
• Yokogawa ALE111 – Ethernet communication module
• Yokogawa ADV551 – digital output module
• Yokogawa AAI141 – analog input module

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Popular Yokogawa Models

• Yokogawa ALF111-S51 – FOUNDATION Fieldbus module
• Yokogawa ALF111-S50 – FF-H1 communication module
• Yokogawa ADV161 – digital input module
• Yokogawa ADV551 – digital output module
• Yokogawa CENTUM VP – DCS control platform