ABB TU847 3BSE022462R1 Module Termination Unit for Redundant CI840/CI840A

What Is the ABB TU847 Module Termination Unit?

When your industrial control system demands high availability, the ABB TU847 3BSE022462R1 Module Termination Unit delivers the foundation for redundant field communication. This passive MTU connects two CI840 or CI840A interfaces, providing power supply, electrical ModuleBus, and two rotary switches for station address settings (0 to 99). Mechanical keying with 36 combinations prevents incorrect module insertion, ensuring reliable operation in critical processes.

Technical Specifications Breakdown

The TU847 operates on a 24 V d.c. power input (19.2 – 30 V) and supports PROFIBUS DP-V1 communication via DSUB9 connectors. It distributes ModuleBus current up to 5 V at 1.5 A and 24 V at 1.5 A. The unit accepts wire sizes from 0.25 to 2.5 mm² (24 – 14 AWG) with a recommended torque of 0.5 – 0.6 Nm and stripping length of 6 – 7.5 mm. Rated insulation voltage is 50 V, with a dielectric test voltage of 500 V a.c. The operating temperature range is 0 to +55 °C (+32 to +131 °F), with storage from -40 to +70 °C (-40 to +158 °F).

Industry Applications

In process industries such as oil and gas, chemical, and power generation, the TU847 enables redundant fieldbus communication for critical control loops. For example, a refinery using CI840A interfaces can rely on the TU847 to maintain PROFIBUS DP-V1 connectivity even if one communication module fails, minimizing downtime. Its vertical or horizontal mounting flexibility suits space-constrained cabinets.

Installation & Setup Guidance

Mount the TU847 on a DIN rail using the integrated latching device for locking and grounding. Connect the 24 V d.c. power supply to the designated terminals. Use DSUB9 connectors for PROFIBUS and RJ45 connectors for service ports. Set the station address via the two rotary switches. Note that the unit cannot be replaced with power applied, and it requires space to the left for removal. Mechanical keys must be configured for the correct module type before installation.

Maintenance & Reliability

As a passive unit, the TU847 requires minimal maintenance. Inspect connections periodically for tightness and verify that the DIN rail latch remains secure. Operate within the specified temperature range (0 to +55 °C) and relative humidity (5 to 95%, non-condensing) to ensure long-term reliability. For vertical mounting, the maximum ambient temperature is 40 °C (104 °F).

Compatibility & Integration

The TU847 is designed for redundant configurations with ABB CI840 or CI840A field communication interfaces. It supports PROFIBUS DP-V1 protocol and can connect to a ModuleBus Optical Port via TB842 and TB806. The unit is CE marked and carries multiple marine certificates (ABS, BV, DNV-GL, LR). It complies with EU, UAE, and CN RoHS, as well as WEEE Directive 2012/19/EU.

Selection Guide & Purchasing Advice

Before ordering, verify that your system uses CI840 or CI840A modules and requires PROFIBUS DP-V1 communication. Confirm the power supply voltage (24 V d.c.) and available DIN rail space (width 124 mm, height 186 mm, depth 47 mm). The TU847 weighs 0.5 kg (1.1 lbs). For G3 compliant environments, consider the TU847Z variant. Contact BluePLC Industrial for current availability and lifecycle status.