ABB TU890 3BSC690075R1 Termination Unit MTU

ABB 3BSC690075R1 TU890 Compact Module Termination Unit

Product Introduction

The ABB 3BSC690075R1 also known as TU890 serves as a compact MTU within the S800 I/O family. You use this passive unit to connect field wiring and process voltage directly to I/O modules. Additionally, it contains a part of the ModuleBus for communication. The TU890 distributes the ModuleBus to the connected I/O module and also forwards it to the next MTU in line. Furthermore, it shifts outgoing position signals to generate the correct address for each I/O module.

This termination unit works with specific I/O modules for intrinsic safety applications. For instance, you can pair it with AI890, AI893, AI895, AO890, AO895, DI890, and DO890. Mechanical keying on the 3BSC690075R1 prevents you from inserting the wrong module type. As a result, installation errors are significantly reduced.

Technical Specifications

The ABB TU890 features 8 channels per unit. It operates on 24V power. Maximum rated voltage is 50V, while maximum rated current reaches 2A per channel. However, the actual I/O module design may impose lower limits for certified applications. Process connections use 27 blue terminals. This MTU supports only single I/O configuration (not redundant).

Acceptable wire sizes for the process connector are as follows. Solid wire ranges from 0.2 to 4 mm². Stranded wire ranges from 0.2 to 2.5 mm² (24 to 12 AWG). Recommended torque for tightening is 0.5 to 0.6 Nm. For the power supply connector, wire sizes from 0.25 to 2.5 mm² (24 to 14 AWG) are acceptable with the same torque recommendation. Dielectric test voltage stands at 500V AC.

Environmental & Certification Data

The 3BSC690075R1 operates from 0°C to +55°C. Storage temperature ranges from -40°C to +70°C. Relative humidity can be 5% to 95% non-condensing. Maximum ambient temperature is 55°C for horizontal mounting. For vertical mounting, this limit drops to 40°C. Protection class is IP20 according to IEC 60529.

This module carries extensive certifications. CE mark is present. Electrical safety follows EN 61010-1 and EN 61010-2-201. For hazardous locations, it meets ATEX/IECEx Zone 2 with interface to Zone 0. It also holds cFMus Class 1, Division 2/Zone 2 with interface to Class 1,2,3 Division 1/Zone 0. Marine certifications include ABS, BV, DNV-GL, and LR. Corrosion protection meets ISA-S71.04 G3 standards. RoHS compliance follows EN 50581:2012.

Mechanical Dimensions

Width measures 64 mm including the connector. Edge-to-edge installed width is 58.5 mm. Depth reaches 58 mm, or 106 mm including terminals. Height is 194 mm including the latch. Weight is only 0.17 kg (0.37 lbs). These compact dimensions save valuable cabinet space.

Frequently Asked Questions (FAQ)

1. Which I/O modules work with the ABB 3BSC690075R1?
The TU890 works exclusively with AI890, AI893, AI895, AO890, AO895, DI890, and DO890 for intrinsic safety applications.

2. Can I use the TU890 for redundant I/O configurations?
No, the ABB TU890 supports only single I/O configurations. For redundant setups, you need a different MTU model.

3. What is the maximum current per channel on this unit?
Maximum rated current is 2A per channel. However, the connected I/O module may specify lower limits for its certified application.

4. Is the TU890 compatible with vertical DIN rail mounting?
Yes, vertical mounting is allowed. But the maximum ambient temperature drops from 55°C to 40°C for vertical orientation.

5. Does the package include the terminal blocks?
Yes, the 3BSC690075R1 comes with all 27 blue process terminals and the power supply connector pre-installed. You only need to connect your wires.