TK851 ABB 3BSC950192R1 CEX-Bus Extension Terminator

Product Overview

The ABB TK851 (Product ID: 3BSC950192R1) functions as the essential CEX-Bus terminator within the ABB AC 800M controller architecture. It provides the necessary electrical impedance matching at the end of a Communication Expansion (CEX) bus string. When engineers extend the CEX-bus using the TK850V007 cable, the system requires the TK851 to prevent signal reflections and maintain high-speed data integrity across the backplane. This compact termination plug ensures that the controller accurately communicates with all interconnected expansion modules. We supply the TK851 as 100% brand new and original, delivering the reliable Swedish-engineered performance required for mission-critical DCS environments.

Technical Specifications

Engineering Advantages

The TK851 3BSC950192R1 solves critical signal integrity challenges in expanded controller racks:

• Elimination of Signal Reflection: High-speed communication buses often suffer from "echoes" or signal reflections at an open cable end. The TK851 terminates the bus with the correct resistive load, ensuring clean square-wave signals for all CEX-bus modules.

• Mandatory Extension Component: When deploying the TK850V007 0.7m extension cable, the bus electrical characteristics change. The TK851 acts as the balancing component, maintaining the 40,000 kbit/s throughput required by the AC 800M family.

• Robust Industrial Durability: Designed to match the temperature ratings of the AC 800M processor, the TK851 operates reliably from –25 °C up to +70 °C. This resilience prevents bus failures caused by thermal expansion or component degradation in harsh process environments.

• Plug-and-Play Installation: The terminator features a standardized connector that secures directly to the bus port. This mechanical fitment ensures a low-resistance electrical contact, which is vital for maintaining the low-error-rate data pathways necessary for SIL-rated applications.

• Zero-Footprint Integration: Its compact design allows for termination at the end of the rail without interfering with neighboring modules or cable ducting, optimizing space within high-density control cabinets.

FAQs

• Is the TK851 mandatory for every AC 800M system?

  The TK851 is mandatory specifically when you extend the CEX-bus beyond the local baseplate, such as when using the TK850V007 extension cable. An unterminated bus leads to communication timeouts and controller errors.

• Can I use a generic terminator instead of the ABB TK851?

  No. The TK851 3BSC950192R1 contains specific impedance circuitry tuned to the electrical characteristics of the ABB AC 800M CEX-bus. Third-party components may lead to intermittent bus faults.

• What is the condition of this unit?

  We supply only 100% brand new, original ABB hardware. Every TK851 arrives in its original factory-sealed packaging and includes a full 12-month manufacturer warranty.

• How does the TK851 affect the HS code for shipping?

  The unit falls under HS Code 854442 as it is classified as an electric conductor fitted with connectors. We provide all necessary documentation to ensure smooth customs clearance from our Swedish stock or global warehouses.