Yokogawa ARM55D-000 | 32-Channel Mechanical Relay Board

Overview

The ARM55D-000 is a 32-channel mechanical relay interface board manufactured by Yokogawa Electric Corporation for use within the CENTUM VP distributed control system. This unit is designed to safely interface digital I/O modules with field-side devices by providing galvanic isolation through dry-contact mechanical relays.

Installed in a 19-inch rack and connected via Yokogawa FIO subsystem cabling, the board ensures reliable signal switching in electrically noisy industrial environments where protection of control electronics is critical.

Functional Characteristics

The ARM55D-000 relay board converts digital output signals from Yokogawa I/O modules into isolated dry-contact outputs. Each channel uses a normally open “a-contact” mechanical relay, suitable for both single and dual-redundant system architectures.

Mechanical isolation protects upstream control hardware from voltage transients, ground loops, and field wiring faults, making the board suitable for safety-related and mission-critical control circuits.

Technical Specifications

• Model: ARM55D-000
• Product Category: Mechanical Relay Board
• Relay Type: Dry Contact, Normally Open (a-contact)
• Number of Channels: 32
• Rated Control Voltage: 24 V DC
• Maximum Switching Current: 650 mA per channel
• Insulation Resistance: Minimum 10 MΩ at 500 V DC
• Field Wiring Terminals: M4 screw terminals
• Mounting Method: 19-inch rack mount
• Compatible Signal Cables: Yokogawa AKB331 series
• Supported I/O Modules: ADV151, ATD5A digital I/O modules
• System Compatibility: CENTUM VP, FIO subsystem
• Dimensions: 184 × 482 × 132 mm
• Weight: 3.20 lbs

System Integration

The ARM55D-000 is engineered for seamless integration into Yokogawa FIO-based architectures. It is commonly deployed between digital output modules and field actuators such as solenoid valves, contactors, interposing relays, and alarm devices.

The board supports redundant configurations when paired with compatible I/O modules, enhancing system availability in high-reliability installations.

Typical Applications

Chemical and petrochemical processing plants Oil and gas production and refining facilities Thermal and nuclear power generation Food and beverage manufacturing systems Process safety and interlock circuits

Model Clarification

The ARM55D series includes multiple variants. While the ARM55D-000 represents the standard basic type, suffix variations may differ in mounting or redundancy options. Always verify exact suffix compatibility with your CENTUM VP system revision prior to procurement.

FAQ

What type of contacts does the ARM55D-000 use The board provides 32 normally open mechanical dry-contact relay outputs.

Is this board suitable for redundant DCS architectures Yes. When used with compatible Yokogawa digital I/O modules, the board supports single and dual-redundant configurations.

Does the board provide electrical isolation Yes. Each relay channel provides galvanic isolation between control-side electronics and field wiring.

Which signal cables are required The board is designed for use with Yokogawa AKB331 series signal cable assemblies.