Description

Yokogawa SARM55D FIO Relay Terminal Board

Configured for discrete relay output interfacing in CENTUM VP and CENTUM CS 3000 FIO subsystem, the Yokogawa SARM55D (SARM55D Relay Board / Terminal Board) provides direct physical/electrical execution of 32-point dry contact switching between DCS output modules and field loads.

The module implements mechanical relay contact architecture with channel separation for low-level control signal conversion to external switching circuits. It is designed for rack-mounted installation with high-density terminal integration and redundant configuration support.

Suffix Breakdown & Model Matrix

No suffix variants or extended ordering matrix information is defined for the SARM55D base model in the provided dataset. Configuration is treated as a single-standard 32-point relay terminal board design.

Hardware Specifications

Parameter	Specification
ModelBrand	Yokogawa SARM55D
Weight	approx. 2.2 kg
Dimensions	482.6 mm x 132.5 mm
OperatingTemp	0 to 50 degC
ProductType	Relay Output Terminal Board (FIO)
Channel Capacity	32 points
Contact Type	Mechanical relay dry contact (NO a contact)
Wiring Interface	M4 screw terminals
Cable Compatibility	AKB331 (32-point), AKB337 (64-point)
Insulation Resistance	>= 10 MOhm at 500 V DC
Withstanding Voltage	2 kV AC field-to-case (1 min), 500 V AC 24 V to case (1 min)

Yokogawa DCS Field Interface Electrical Characteristics

The SARM55D implements channel-level galvanic separation between field wiring and internal FIO logic domain. Output switching is executed via mechanical relay contacts driven from ADV-series I/O modules such as ADV561, ensuring physical isolation of control logic from field-side voltage transients. The terminal structure supports high-density routing of 32 discrete output channels with reduced cross-channel coupling within the rack backplane architecture.

Frequently Asked Questions

Q: Can the SARM55D support hot-swap replacement under live DCS operation?
A: Hot-swap capability is not defined at relay terminal board level; replacement requires system-level isolation of FIO power and output loop de-energization.

Q: What is the maximum electrical isolation level between field terminals and internal circuitry?
A: The insulation system is specified for 2 kV AC withstand between field terminals and case for 1 minute under standard test conditions.

Q: Is channel-to-channel electrical isolation individually implemented?
A: Isolation is primarily implemented between field-side and system-side domains; internal relay grouping governs channel separation behavior.

Field Installation Guidelines

Ensure all field wiring is terminated using M4 screw torque specifications consistent with industrial control cabinet standards. Maintain segregation between high-voltage switching lines and low-level signal routing to minimize induced noise coupling. Shielded cable grounding should be terminated at a single control panel earth reference point to avoid ground loop formation. Verify all relay output loops are de-energized prior to insertion or removal of the terminal board. Maintain minimum bend radius for AKB-series cables during rack integration to avoid mechanical stress on connector interfaces.

Specifications

• Brand: Yokogawa

Advantages

• High reliability in industrial environments
• Supports continuous operation
• Compatible with major PLC/DCS systems