ABB 3BDZ000398R1 RLM01 PROFIBUS Redundancy Link Module

Product Description

The ABB RLM01 (3BDZ000398R1) is a PROFIBUS redundancy link module for industrial automation systems.
It converts a single PROFIBUS line into two redundant lines, preventing single points of failure.
Moreover, it supports high-speed communication from 9.6 Kbps to 12 Mbps with integrated diagnostics for reliability.

RLM01 Technical Overview

Serial Interfaces

Data Telegram Delay

• A/B → M: 1 Bit time [µs] + 0.6 µs

• M → A/B: 4 Bit times [µs] + 0.6 µs

Power Supply

Ambient Conditions

Alarm Contact

Design

Certification

Installation Guidelines

• Redundant Power Supply: To achieve maximum reliability, use both 24 VDC inputs from independent power sources.

• Telegram Delay Calculation: When calculating the total PROFIBUS cycle time (TTR), ensure the specific bit-time delays ($1 \text{ Bit } + 0.6 \mu s$ and $4 \text{ Bits } + 0.6 \mu s$) are accounted for, especially in high-speed 12 Mbit/s configurations.

• Termination: Each segment (A, B, and M) must be correctly terminated using active terminators or standard PROFIBUS connectors with termination switches.

• Maritime Installation: For shipboard use, a 24 VDC surge filter is mandatory to comply with Germanischer Lloyd (GL) standards.

Frequently Asked Questions (FAQs)

Q1: Is the RLM01 "transparent" to the protocol?

A: Yes. It operates at the physical layer (Layer 1). It does not require a GSD file, station address, or software configuration. It purely manages signal routing between A/B and M.

Q2: What causes the Alarm Contact to open?

A: The alarm contact typically indicates a loss of power (either Input 1 or 2) or a signal failure on one of the redundant PROFIBUS lines (Line A or Line B).

Q3: Can I mix different brands of PROFIBUS equipment?

A: Yes. Because it adheres to the RS-485 standard and is protocol-transparent, the RLM01 can bridge any standard PROFIBUS DP Master/Slave regardless of the manufacturer.

Q4: How does the delay affect my network?

A: The delay is minimal (a few bit times). However, in very large networks with multiple repeaters, you may need to adjust the "Slot Time" in your PLC/Master hardware configuration to prevent timeouts.