Overview

The ABB RMU811 Symphony Plus Repeater is not a standalone repeater module but a mounting base designed to host two RFO810 modules in a redundant configuration. It plays a vital role in extending the HN800 bus communication over fiber optics, enabling long-distance and EMI-resistant data transmission in distributed control systems.

Moreover, RMU811 simplifies installation by integrating power distribution and HN800 connectors directly into the base. This ensures clean wiring, reliable signal routing, and easy maintenance. In addition, its compact form factor and DIN rail compatibility make it ideal for control cabinets in power generation, water treatment, and process automation facilities.

For instance, in a Symphony Plus system, RMU811 allows SD Series controllers to communicate with remote I/O racks up to 3 km away using RFO810 repeaters. Therefore, it’s essential for scalable and fault-tolerant network architecture.

Technical Data

Sources

Typical Applications

• Symphony Plus SD Series Networks: Extends HN800 bus communication using fiber optics for remote I/O connectivity.

• Power Generation Facilities: Supports long-distance control signal transmission in turbine and substation systems.

• Water and Wastewater Plants: Enables distributed control across large treatment areas.

• Process Automation Systems: Facilitates EMI-resistant communication in chemical and manufacturing environments.

• Redundant Network Architectures: Hosts dual RFO810 modules for fault-tolerant fiber links.

In addition, RMU811 helps reduce installation time and ensures consistent performance by integrating power and bus connectors into a single base.

FAQ

Q: Is RMU811 a repeater module?
A: No, it’s a mounting base for two RFO810 fiber optic repeater modules.

Q: What systems is it compatible with?
A: It supports Symphony Plus SD Series controllers and HN800 bus networks.

Q: What power supply does it require?
A: It operates on 24 V DC with a current rating of 0.2 A.

Q: Can it be DIN rail mounted?
A: Yes, it’s designed for DIN rail installation in control cabinets.

Q: What is the maximum communication distance supported?
A: With RFO810 modules, it supports up to 3 km of fiber optic communication.