The ABB RLM02 (3BSE091723R1) is a PROFIBUS DP/FMS Redundancy Link Module designed to provide cable redundancy for PROFIBUS communication networks. It functions as an active repeater and switch, converting a single non-redundant PROFIBUS RS-485 line into two redundant communication lines (A/B), or vice versa. This ensures high-availability communication by automatically switching to the healthy path if a cable or segment fails, preventing downtime in critical automation systems.

Features

• Supports PROFIBUS DP and FMS protocols.
• Transmission rates from 9.6 kbit/s to 12 Mbit/s.
• Active repeater functionality for signal regeneration.
• Automatic line selection and monitoring of communication quality.
• Redundant power supply support with potential-free alarm contact.
• Status LEDs for bus activity, errors, and power supply monitoring.
• Simple DIN-rail mounting.

Applications

• Turbine Generators (Gas/Steam/Hydro).
• Boiler Control Systems and redundant combustion loops.
• Emergency Diesel Generators (EDGs).
• Large-Scale Compressors and Pumps for oil/gas pipelines.
• Industrial Kilns and Furnaces.
• Water Treatment Machinery and automated filtration systems.

Technical Specifications

Installation Guidelines

• Ensure the module is mounted on a standard DIN rail in an appropriate enclosure (IP20 rated).
• Maintain an ambient operating temperature between 0 degC and +55 degC with adequate ventilation.
• Ensure all PROFIBUS cables are properly shielded and grounded according to standard industrial practices to prevent EMI.
• The module provides functional electrical isolation; ensure power supply connections are secure and polarity is correct.
• Always power down the system before inserting or removing the module from the DIN rail.
• The potential-free alarm contact can be wired to a PLC or DCS input for diagnostic monitoring of module health.

FAQ

What is the ABB RLM02 3BSE091723R1?

The ABB RLM02 is an active switch that integrates single-interface PROFIBUS devices into a redundant RS485 PROFIBUS network, ensuring fault-tolerant communication.

How does it handle communication faults?

The module monitors lines A, B, and M for activity. If an error is detected on one of the redundant lines, the logic automatically switches to the operational path without interrupting data exchange.

What is the maximum number of connected devices?

Each RLM02 PROFIBUS interface can support up to 31 PROFIBUS stations.