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Yokogawa SCP461-CESSOS2
Model Number: SCP461-CESSOS2
Product Introduction:
The SCP461-CESSOS2 is a serial communication interface module designed for the CENTUM VP and CENTUM CS3000 Distributed Control Systems (DCS). It enables high-speed data exchange between the DCS controller and field devices, PLCs, and other system components using standard serial communication protocols.
Detailed content
Function Features:
- Supports EIA RS-232C and RS-485 dual-protocol communication simultaneously
- Provides galvanic isolation between the DCS bus and external communication lines
- Enables point-to-point and multi-drop network topologies
- Supports Modbus RTU (Master/Slave) protocol operation
- Compatible with CENTUM VP HIS (Human Interface Station) and FCS (Field Control Station)
- Facilitates remote configuration and diagnostics of field instruments
Technical Specifications:
| Parameter | Specification |
|---|---|
| Communication Protocol | EIA RS-232C / RS-485 |
| Baud Rate | 1200 / 2400 / 4800 / 9600 / 19200 / 38400 bps |
| Data Format | 7 or 8 data bits, 1 or 2 stop bits, even/odd/no parity |
| Isolation Voltage | 1500 V AC (50/60 Hz) for 1 minute |
| Power Supply | 24 V DC (±10%) from DCS backplane |
| Operating Temperature | 0°C to +55°C |
| Dimensions (W×H×D) | 25.4 × 120 × 160 mm (approx.) |
| Weight | Approximately 0.3 kg |
| Compliance Standards | IEC 61131-2, FCC Part 15 Class A, CE Marking |
Structure Characteristics:
- DIN rail or panel-mount installation compatible
- 32-pin connector for DCS backplane interface
- Screw-terminal blocks for external RS-232C/RS-485 wiring
- LED status indicators for power, communication activity, and error states
- DIP switches for address and protocol configuration
Working Principle:
The module receives data packets from the DCS controller via the system bus (Vnet/FNET), converts the data into serial format (RS-232C or RS-485), and transmits it to external field devices. Incoming serial data is converted back to DCS-compatible format and forwarded to the appropriate control station. Galvanic isolation protects the DCS backplane from electrical surges and ground loops on the field side.
Advantages & Highlights:
- Dual-protocol support eliminates need for separate communication cards
- Built-in galvanic isolation ensures system reliability in electrically noisy environments
- Hot-swappable design allows module replacement without system shutdown
- Wide baud rate range supports both legacy and modern field devices
- Modbus compatibility ensures interoperability with third-party equipment
Applicable Industries:
- Oil & Gas (refineries, pipelines, offshore platforms)
- Chemical & Petrochemical processing plants
- Power Generation (thermal, nuclear, combined cycle)
- Pharmaceutical manufacturing
- Pulp & Paper mills
- Water & Wastewater treatment facilities
Installation Requirements:
- Install in DIN rail enclosure or control panel with adequate ventilation
- Maintain minimum 10 mm clearance above and below the module for airflow
- Use shielded twisted-pair cables for RS-485 communication runs exceeding 10 meters
- Connect shield ground at one end only to prevent ground loops
- Ensure 24 V DC power supply stability within ±10% tolerance
Usage Precautions:
- Do not exceed 1500 V AC isolation rating between communication ports and DCS backplane
- Terminate RS-485 bus with 120Ω resistor at both ends for runs over 100 meters
- Avoid routing communication cables parallel to high-voltage power cables (minimum 200 mm separation)
- Do not connect RS-232C and RS-485 ports simultaneously to the same external device
- Firmware updates must be performed through CENTUM VP Engineering Station only
