Product Overview

The TU846 3BSE022460R1 is a high-availability Module Termination Unit (MTU) engineered specifically for the ABB S800 I/O system's redundant configurations. This passive unit serves as the essential mounting foundation for dual CI840 or CI840A Field Communication Interfaces (FCI). By providing the electrical and mechanical pathways for synchronized communication, the TU846 ensures that control data remains uninterrupted even during a single hardware fault. It integrates power distribution, redundant ModuleBus connectivity, and physical addressing into a single, space-efficient chassis, making it a cornerstone for systems where process uptime is non-negotiable.

Critical Hardware Metrics and Interface Details

The TU846 is designed for maximum connectivity and fail-safe operation within high-density Distributed Control System (DCS) environments.

• Redundancy Support: Dual-slot capacity for CI840/CI840A field communication units.

• Network Interfacing: Equipped with two PROFIBUS connections and two dedicated service tool ports.

• Addressing System: Features dual rotary switches for manual station address assignment (Range 0-99).

• Bus Architecture: Supports two electrical ModuleBuses and is compatible with TB842 Optical Port expansion.

• Physical Profile: 12.7cm x 5.1cm x 20.3cm.

• Unit Mass: 0.3 kg.

• Safety Mechanism: Four mechanical keys (two per position) offering 36 unique coding variables to prevent incorrect module insertion.

• Mounting & Grounding: Integrated 35mm DIN rail latching system with automatic functional grounding.

Strategic Industrial Implementations

This redundant termination unit is a fundamental component for mission-critical automation in heavy industries. In the oil and gas and petrochemical sectors, the TU846 is utilized to maintain constant communication between field instrumentation and the safety shutdown system, where any loss of signal could lead to costly operational interruptions. It is equally indispensable in power generation facilities for monitoring turbine and boiler sequences, providing the high-reliability backbone required for 24/7 power production. Its rugged Swedish engineering ensures long-term stability in high-vibration environments, while the ability to facilitate redundant I/O clusters allows maintenance teams to perform hardware swaps without de-energizing the entire control loop.