ABB TB807 3BSE008538R1 Modulebus Terminal Unit

Product Overview

The TB807 (3BSE008538R1) is a critical termination module for the ABB S800 I/O system, providing precise impedance matching for the electrical Modulebus. By closing the communication loop at the physical end of the I/O cluster, it eliminates signal reflections and electromagnetic interference. This unit is essential for maintaining data integrity and ensuring high-speed communication stability between the controller and distributed I/O stations.

Technical Specifications

• Brand: ABB

• Product Series: S800 I/O

• Model Name: TB807

• Part Number: 3BSE008538R1

• Function: Modulebus Signal Termination

• Corrosion Resistance: ISA-S71.04 G3 Conformal Coating

• Operating Temperature: 0 to +55 °C

• Storage Temperature: -25 to +70 °C

• Relative Humidity: 5 to 95% (Non-condensing)

• Hazardous Ratings: ATEX Zone 2, Class I Div 2 cULus

• Marine Approvals: ABS, BV, DNV, LR

• Electrical Safety: IEC 61131-2, UL 61010-1

• EMC Standards: EN 61000-6-4 (Emission), EN 61000-6-2 (Immunity)

• Protection Class: IP20 (IEC 60529)

• Pollution Degree: Degree 2 (IEC 60664-1)

Engineering Insights and Operational Logic

The TB807 (3BSE008538R1) is a passive but mandatory hardware component for every S800 I/O cluster. In high-speed serial communication, an unterminated bus behaves like an electrical mirror, reflecting signals back into the line and causing "data collisions" or "Modulebus Fail" errors. The TB807 absorbs this residual energy to maintain a clean signal waveform. Featuring G3-level protection, this module is specifically hardened against harsh atmospheric conditions (such as hydrogen sulfide and chlorine), making it the standard choice for offshore platforms, refineries, and heavy industrial applications.