Description

The TU847 (Order Code: 3BSE022462R1) is a specialized Module Termination Unit (MTU) manufactured by ABB, designed to support the CI840 and CI840A field communication interfaces. It serves as a critical hardware component for establishing PROFIBUS DP redundancy, allowing industrial networks to maintain communication even if a primary cable path fails.

Functioning as a redundancy link module, the TU847 provides the necessary mechanical and electrical foundation for high-availability configurations. It features dual PROFIBUS connectors and mechanical keying, ensuring that the correct communication modules are installed and that the network remains stable in demanding process automation environments.

Application Scenarios

Consider a large-scale pulp and paper mill where a continuous production line relies on hundreds of distributed drives communicating via PROFIBUS DP. In this environment, a single severed cable could halt the entire line, costing thousands of dollars per minute. The TU847 solves this by enabling a redundant ring or dual-bus architecture.

In this setup, the TU847 acts as the gateway that converts a single bus signal into a redundant dual-bus system (or vice versa). If the primary communication cable is damaged, the TU847 ensures the signal is instantly rerouted through the secondary path. This “fail-safe” capability ensures that the CI840 interface maintains a continuous link with the PLC, preventing costly production stoppages and ensuring operational continuity.