Description

Yokogawa SNB10D-225/CU2T Safety Node Unit

Configured for safety I/O expansion and ESB bus communication in the ProSafe-RS Safety Instrumented System, the Yokogawa SNB10D-225/CU2T (SNB10D Safety Node Unit) provides direct physical and electrical execution of remote safety signal interfacing between field-connected I/O modules and Safety Control Units through a dual-redundant Extended System Bus architecture.

Suffix Breakdown & Model Matrix

Parameter	Specification
Base Model	SNB10D
Product Type	Safety Node Unit, Rack-Mountable Type
Suffix Code 1	2 = Dual-redundant power supply with node expansion software license
Suffix Code 2	2 = 220 to 240 VAC power supply
Suffix Code 3	5 = ISA G3 environmental specification, -20 to 70 degC
Option Code	/CU2T = Connector Unit with ESB Bus Terminator
Connector Unit Part No.	S9343FA

Hardware Specifications

Parameter	Specification
Model	SNB10D-225/CU2T
Brand	Yokogawa
Origin	Japan
Product Type	Safety Node Unit
Mounting Method	19-inch rack mounting
Dimensions	482.6 mm x 132.5 mm x 205 mm
Weight	5.9 kg
Power Supply	220 to 240 VAC, 50/60 Hz
Power Consumption	230 VA maximum
Power Redundancy	Dual-redundant internal power supplies
Operating Temp	-20 to 70 degC
Relative Humidity	5% to 95% RH, non-condensing
Environmental Rating	ISA-S71.04 G3
Withstanding Voltage	1500 VAC between power terminal and ground for 1 minute
ESB Bus Interface	Connector Unit with integrated terminator
System Expansion	Up to 9 units via SEC401, up to 13 units via SEC402
Supported Modules	ProSafe-RS safety I/O modules
Standard Accessories	Four S9049PM insulating bushings

Channel Isolation and Safety Signal Integration

Within ProSafe-RS architectures, the SNB10D Safety Node Unit functions as an intermediary platform for safety-related digital and analog I/O modules. Signal transmission between the node unit and the associated Safety Control Unit is performed through the Extended System Bus (ESB) using redundant communication paths.

The rack incorporates dual power inputs and automatic power-source switchover capability. The /CU2T configuration includes a dedicated ESB termination assembly that provides bus-end matching for the communication segment. Installation is intended inside a metallic control cabinet to maintain EMC compliance and system grounding requirements.

Frequently Asked Questions

Q: Does the SNB10D-225/CU2T support redundant power operation?
A: Yes. The unit includes dual-redundant internal power supply functionality. If one power source becomes unavailable, operation continues through the remaining power supply path.

Q: Is external ESB bus termination required when the /CU2T option is installed?
A: No. The /CU2T option includes a Connector Unit with an integrated ESB bus terminator, providing end-of-line termination within the supplied assembly.

Q: Can the SNB10D be mounted directly in an open industrial area?
A: No. Installation documentation specifies mounting within a keyed metallic enclosure to satisfy EMC and safety compliance requirements.

Field Installation Guidelines

• Mount the unit in a standard 19-inch rack using the specified insulating bushings supplied with the chassis.
• Verify incoming supply voltage is within the 220 to 240 VAC operating range before energizing the node.
• Route ESB communication cables separately from high-power conductors to reduce conducted electrical interference.
• Maintain cabinet grounding in accordance with plant grounding standards and Yokogawa installation practices.
• Install the /CU2T connector assembly at the designated ESB bus termination location.
• Ensure adequate cabinet ventilation when operating near the upper temperature limit of 70 degC.
• Confirm all I/O modules are approved ProSafe-RS compatible modules before insertion into the node assembly.

Specifications

• Brand: Yokogawa

Advantages

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