SARM55C | Yokogawa Terminal Board (Mechanical Relay Dry Contact Output NO/NC)

Product Overview

The SARM55C is a mechanical relay dry contact output terminal board providing 32 points configurable as “a” (NO) or “b” (NC) contacts. It interfaces digital output modules (ADV551/ADV561) to field devices in CENTUM VP systems.

Key Features

• 32 dry contact output points
• Configurable NO or NC contacts
• M3.5 screw terminals (M4 for power)
• Single or dual-redundant support
• High isolation performance

Technical Specifications

• Contact Points: 32
• Contact Type: Dry contact (“a” NO or “b” NC)
• Terminals: M3.5 screws (M4 for power input)
• Maximum Load: 250 V AC 2 A, 30 V DC 2 A, 125 V DC 0.1 A per point
• Minimum Load: 5 V, 10 mA
• Internal Power: 24 V DC, max 0.85 A
• Insulation Resistance: ≥10 MΩ at 500 V DC
• Withstanding Voltage: 2 kV (field to case), 500 V (power to case), 2 kV (power to field)
• Dimensions: 482.6 mm (W) × 132.5 mm (H) (3U)
• Weight: Approx. 2.2 kg
• Ambient: 0 to 50 °C, 10 to 90 %RH

FAQ

• Can contacts be configured as NO or NC? Yes, both “a” and “b” contacts are available.
• What modules does it work with? ADV551 (32-point) and ADV561 (64-point).
• What is the maximum switching current? 2 A at 250 V AC or 30 V DC.

Installation Guide

1. Install the board in a 19-inch rack.
2. Connect the AKB331 or AKB337 signal cable to the digital output module.
3. Wire field loads to the M3.5 terminals according to NO/NC requirements.
4. Connect external 24 V DC power.
5. Verify relay operation and isolation after power-up.

Selection Tips

• Choose when configurable NO/NC dry contacts are required.
• Confirm load ratings match the field devices.
• Verify terminal screw size preference (M3.5).