Product Overview
The Yokogawa YCB147-2 is a passive control bus cable conversion adapter designed for Yokogawa CENTUM VP, CENTUM CS 3000, and ProSafe-RS safety instrumented system architectures. As a critical physical-layer interface device, the Yokogawa YCB147-2 bridges different control bus cable types—specifically converting between V net 10BASE-5 coaxial cabling and 10BASE-2 thin coaxial connections—enabling seamless communication across disparate bus segments without signal degradation or software configuration.
The Yokogawa YCB147-2 serves as the hardware bridge that normalizes physical connection interfaces between the V net control network, ESB safety bus, and ER remote I/O bus. By providing precise impedance matching and built-in bus termination, the adapter eliminates signal reflection issues that commonly plague long cable runs in distributed control systems. This function is essential when integrating legacy bus segments with modern CENTUM VP controllers, allowing plants to expand their automation footprint without replacing existing functional cabling infrastructure.
The -2 suffix designates a two-connector, standard (non-explosion-proof) configuration, distinguishing the Yokogawa YCB147-2 from variants such as the YCB147-6 (four-connector) and YCB147-F (explosion-proof) models. The adapter operates entirely passively, requiring no external power supply, which eliminates power-related failure modes and contributes to long-term reliability in continuous process environments. The optional /BR suffix denotes a 19-inch rack-mount configuration for standardized cabinet installation.
Technical Specifications
| Parameter Name | Parameter Value |
|---|---|
| Product Model | Yokogawa YCB147-2 |
| Manufacturer | Yokogawa Electric Corporation |
| Product Type | Control Bus Cable Conversion Adapter |
| Function | V net (10BASE-2/10BASE-5), ESB, ER bus interface conversion |
| Connector Count | 2 (standard type) |
| Power Requirement | Passive, no external supply required |
| Supported Bus Types | V net (10BASE-2/10BASE-5), ESB (128 Mbps), ER bus |
| Built-in Termination | Yes, integral bus terminal resistor |
| Signal Latency | Negligible, transparent to real-time control |
| Operating Temperature | 0°C to +60°C (extended range: -10°C to +55°C) |
| Storage Temperature | -40°C to +85°C |
| Humidity | 5% to 95% RH, non-condensing |
| Protection Rating | IP20 (cabinet interior installation) |
| Mounting | Panel mount; /BR option for 19-inch rack |
| Dimensions | Approx. 145 × 42 × 115 mm |
| Weight | Approx. 0.32 kg |
| System Compatibility | CENTUM VP, CENTUM CS 3000, ProSafe-RS |
Main Features and Advantages
Multi-Bus Physical Layer Conversion: The Yokogawa YCB147-2 functions as a signal bridge between incompatible bus cable media types. Its primary role is converting between 10BASE-5 thick coaxial cable used on V net backbones and 10BASE-2 thin coaxial cable used for local device connections. This capability is essential when integrating CENTUM VP or CS 3000 equipment with ProSafe-RS safety systems, where the safety engineering PC and safety control unit use 10BASE-2 cabling while the DCS may employ 10BASE-5 infrastructure.
Built-in Termination Eliminates Signal Reflection: The Yokogawa YCB147-2 incorporates internal bus terminal resistors that provide precise impedance matching at the conversion point. This prevents signal “bounce” or reflection across long cable runs—a common cause of intermittent communication timeouts and CRC errors in complex DCS networks. By delivering clean, terminated signal paths, the adapter allows DCS diagnostic software to accurately identify genuine hardware faults rather than generating false alarms from poor cable matching.
Passive Design for Maximum Reliability: Operating without external power, the Yokogawa YCB147-2 introduces no additional failure points related to power supply components. This passive architecture ensures that the adapter itself cannot become the root cause of a network outage, contributing to the overall availability of the control system. The absence of active components also means zero heat generation and no firmware or software that could require maintenance or updates.
Legacy-to-Modern System Integration: The Yokogawa YCB147-2 enables plants to integrate older ESB or ER bus components with current-generation V net controllers without replacing existing functional cabling. This capability is particularly valuable for system upgrades and expansions, where the adapter eliminates the physical connectivity gap between legacy field infrastructure and modern control hardware.
