Product Overview

The ABB TB807 (3BSE008538R1) is a precision-engineered Modulebus terminator designed for the S800 I/O system, critical for maintaining electrical integrity and reliable communication between the AC 800M controller and connected I/O modules. This passive unit prevents signal reflections at the end of the Modulebus, ensuring stable and error-free data transfer across the I/O network.

Key Features

Signal Integrity Maintenance
The TB807 provides matched impedance termination at the end of the Modulebus, preventing signal reflections and preserving clean, high-speed digital signals across all modules in the I/O cluster.

Plug-and-Play Installation
Equipped with a standard Modulebus connector, the TB807 simply plugs into the last I/O module carrier (TU810, TU830, or equivalent), requiring no software configuration.

Compact, Robust Construction

• Vibration Resistant: Locks securely into the I/O base, preventing disconnection.

• Space-Efficient: Minimal footprint preserves DIN rail space for active I/O modules.

Passive Operation
The terminator requires no external power, contributing zero thermal load and drawing no current from the system.

Enhanced System Reliability
By stabilizing bus impedance, TB807 improves overall MTBF, reducing intermittent communication errors and preventing "Module Missing" or "I/O Fault" alarms in the 800xA control environment.

Technical Specifications

Applications

S800 I/O Bus Termination: Ensures signal stability in AC 800M controller setups.

Critical Control Systems: Ideal for systems where uninterrupted I/O communication is required, including factory automation, building control, and process monitoring.

Clustered Module Configurations: Necessary at the physical end of any Modulebus string, including multi-cluster or fiber-extended setups.

Installation Guidelines

• Every Modulebus string must be terminated with a TB807 or equivalent device.

• Insert the terminator at the last module of the cluster to maintain signal integrity.

• Failure to install a proper terminator may cause I/O errors or prevent modules from being recognized.

Frequently Asked Questions (FAQ)

Q: Is power required for TB807 operation?
A: No, the TB807 is a passive component and does not consume power.

Q: Can it be used with all S800 I/O clusters?
A: Yes, it is compatible with any S800 I/O cluster requiring Modulebus termination.

Q: Are there similar terminators for comparison?
A: TB808 and TB809 are other ABB Modulebus terminators designed for alternative I/O or high-reliability configurations.