Description

The ABB TU845 (3BSE021447R1) is a high-performance Module Termination Unit (MTU) designed for the S800 I/O system. This unit serves as the interface for field wiring, supporting redundant I/O configurations. It facilitates the connection of field signals and process power while distributing the ModuleBus to I/O modules. The TU845 is engineered to ensure robust signal integrity and reliable process control in demanding industrial environments.

Features

• Supports up to 8 I/O channels with 2-wire connections.
• Provides 2+2 process voltage connections for field power distribution.
• Redundant design for enhanced system availability.
• Integrated mechanical keying system with 36 possible configurations to prevent incorrect module insertion.
• Latching mechanism for secure DIN rail mounting and integrated grounding.
• Compatible with individual shunt sticks (TY801) for flexible voltage or current input selection.

Technical Specifications

Applications

• Oil and Gas: Offshore platforms and natural gas transmission stations.
• Refining and Petrochemicals: Large-scale ethylene and chemical processing plants.
• Power Generation: Thermal, hydroelectric, and waste-to-energy facilities.
• Water Treatment: Urban water supply and sewage treatment control systems.
• Pulp and Paper: Continuous pulping lines and high-speed machine control.

Installation Guidelines

• Ensure the DIN rail is securely mounted and properly grounded before installing the MTU.
• The MTU features a mechanical latch; ensure it is fully engaged to lock the unit onto the DIN rail.
• Verify the mechanical keys are correctly configured for the specific I/O module being used to prevent mismatching.
• Always power down the system before inserting or removing I/O modules from the MTU to prevent electrical damage.
• Route signal cables away from high-EMI sources to maintain signal integrity.
• Ensure adequate ventilation around the module to maintain operating temperatures within the 0 to +55 degC range.

FAQs

What is the primary function of the TU845?

The TU845 is an MTU used for terminating field wiring in a redundant S800 I/O configuration, providing both signal and process power distribution.

Which I/O modules are compatible with the TU845?

The TU845 is designed for use with specific redundant modules, including the AI845, AI880, AI880A, and DP840.

How does the mechanical keying work?

The MTU uses four mechanical keys (two per I/O module) with six positions each, providing 36 unique configurations to ensure only the correct module type can be inserted into a specific slot.