ABB TK850

The TK850 is an expansion cable/module developed by ABB for the CEX (Compact Expansion) bus. It is primarily designed to enable long-distance bus extension and modular connection in the 800xA and System 800xA control systems. When paired with terminals such as the TK851 and TB850/TB851, it facilitates signal transmission either inside a control cabinet or across multiple cabinets.

Key Technical Specifications

• Model: TK850V007 (Common Specification)
• Compatible Bus: CEX Bus (24 V DC-based)
• Cable Type: Shielded twisted pair, supporting 2 × 24 V power supply and signal channels
• Maximum Transmission Distance: Up to 200 m (depending on specific wiring and load conditions)
• Connection Method: Standard CEX terminals (pin or socket type) at both ends, enabling direct plug-and-play operation
• Operating Temperature Range: -20 °C to +60 °C, suitable for industrial environments
• Protection Class: IP20, ideal for internal cabinet installation

Product Features

1. Modular Expansion: Leveraging standardized CEX terminals, the TK850 allows for quick plug-and-play connectivity, making it easy to add or remove I/O modules on-site.
2. High Reliability: Equipped with shielded twisted pair cables and anti-interference design, it ensures signal integrity and complies with industrial communication standards such as IEC 61850.
3. Strong Compatibility: It seamlessly integrates with other ABB CEX components including the TK851, TB850/TB851 and BC810K02, and supports redundant controller connections.
4. Simplified Wiring: A single cable delivers both power and signal, reducing wiring costs and space requirements.
5. Easy Maintenance: The terminal adopts a plug-and-play structure, enabling quick fault location and replacement.

Structure and Components

• Cable Body: Multi-strand shielded copper wire with an outer PVC/PE insulating sheath.
• Terminal Connectors: ABB standard CEX terminals (pin or socket type) at both ends, which can be directly mated with the terminals of the TK851 and TB850/TB851.
• Protective Sleeve: Optional metal or plastic sleeve is available to enhance tensile strength and protective performance.

Typical Application Areas

• Process Automation: Field bus extension for continuous production lines in industries such as chemical engineering, petroleum and natural gas.
• Power Systems: I/O expansion for distribution automation and substation monitoring cabinets.
• Building Automation: Bus extension for HVAC, security and lighting control systems in large-scale buildings.
• Manufacturing Industry: Modular I/O connection for CNC machine tools and robot control cabinets.

Installation and Maintenance Guidelines

Installation

1. Confirm Wiring Path: Determine the cable routing based on the on-site layout, and avoid parallel routing with high-voltage cables to minimize electromagnetic interference.
2. Terminal Matching: Select the corresponding TK850 specification according to the terminal type (pin or socket) used to ensure consistency in terminal types.
3. Fixed Support: Secure the cable with cable clips or brackets, and maintain a bending radius of not less than 10 × the cable diameter to prevent excessive bending.
4. Grounding: If a metal sleeve is used, proper grounding must be implemented to prevent electrostatic accumulation.

Commissioning

1. Use ABB-provided CEX bus diagnostic tools (e.g., CEX Diagnostic Module) to check signal integrity, supply voltage and terminal contact conditions.
2. Conduct a single-port continuity test before system startup to ensure that each cable segment is free of short circuits or open circuits.

Maintenance

1. Regular Inspection: Inspect terminal tightness, sheath integrity, and cable surface for wear or aging every 6 months.
2. Replacement Principle: If outer sheath damage or poor terminal contact is detected, replace the corresponding cable segment promptly to avoid total bus failure caused by local faults.
3. Spare Parts Management: It is recommended to keep supporting terminals such as the TK850, TB850/TB851 and TK851 in stock on-site for quick replacement.