
Product Overview
The Yokogawa SNB10D-425/CU2T Safety Node Unit is a distributed I/O node used in ProSafe-RS Safety Instrumented Systems (SIS). It is responsible for field signal acquisition, ESB bus communication, and power distribution, ensuring stable and reliable operation in safety-critical industrial environments.
The /CU2T configuration indicates a connector unit with ESB termination support, designed to improve signal integrity at the end of the ESB bus line in a safety system network.
Technical Specifications
| Parameter |
Details |
| Manufacturer |
Yokogawa |
| Model |
SNB10D-425/CU2T |
| Product Type |
Safety Node Unit |
| System Platform |
ProSafe-RS SIS |
| Function |
Safety I/O node, ESB communication, power distribution |
| Communication Protocol |
ESB Bus |
| Mounting Type |
19-inch rack mounted |
| Dimensions |
482.6 x 221.5 x 205 mm |
| Weight |
5.9 kg |
| Redundancy Support |
Supported |
| Application |
Industrial safety systems |
Function and Working Principle
The SNB10D-425/CU2T operates as a distributed safety interface node, performing the following functions:
- Collecting analog and digital field signals
- Transmitting safety data via ESB bus
- Supplying power to connected I/O modules
- Supporting redundant and fault-tolerant system architecture
- Providing ESB bus termination for stable communication
System Flow
Field Devices → Safety Node Unit → ESB Bus → Safety Control Unit
Role in Safety Systems
Within Yokogawa ProSafe-RS systems, this unit acts as a local I/O expansion and communication hub, connecting:
- Field transmitters (pressure, temperature, flow, level)
- Emergency shutdown switches
- Digital and analog I/O modules
- Central safety controllers
It helps reduce wiring complexity while maintaining high system reliability.
Industrial Applications
- Oil & gas facilities
- Petrochemical plants
- Refinery systems
- Offshore platforms
- Power generation stations
- Chemical processing plants
- Safety Instrumented Systems (SIS)
- Emergency Shutdown Systems (ESD)
- Fire & Gas systems
Installation
- 19-inch rack mounting
- ESB bus connection required
- Proper grounding and shielding required
- Configuration of termination depends on system design
- System commissioning required for validation
Compatible Components
- Yokogawa ProSafe-RS safety controllers
- ESB bus coupler modules
- Safety I/O modules
- Terminal boards
- Power supply modules
Alternative Models
- SNB10D-425/CU2N (non-termination version)
- SNB10D-415/CU2T
- SNB10D-225/CU2N
- SNB10D-223/CU2N
- SNB10D-243/C2UT
Key Advantages
- High reliability safety architecture
- Supports redundant system design
- Stable ESB communication
- Connector with termination support (/CU2T)
- Modular and scalable system integration
- Suitable for continuous industrial operation
- Designed for SIL-rated environments
FAQ
Q: What is the difference between CU2T and CU2N?
A: CU2T includes ESB termination support, while CU2N is for standard node-to-node connection.
Q: Is this a controller?
A: No, it is a distributed safety I/O node.
Q: Where is it used?
A: It is used in SIS, ESD, and F&G safety systems.
Conclusion
The Yokogawa SNB10D-425/CU2T is a safety node unit designed for distributed control architectures. It ensures reliable ESB communication, stable field signal handling, and robust system integration in industrial safety environments.