Bently Nevada 3500/20-02-02-00 125744-01 TMR Rack Interface Module

Description

The Rack Interface Module (RIM) serves as the primary gateway and processing interface for the 3500 Series machinery protection system. It establishes a connection via a proprietary protocol to facilitate comprehensive rack configuration and real-time machinery data retrieval. Designed exclusively for localized layout tracking, this module must reside in slot 1 of the rack assembly, immediately adjacent to the system power supplies.

This specific configuration 3500/20-02-02-00 functions as a Triple Modular Redundant (TMR) version equipped with a dedicated RS232/RS422 serial I/O interface. Beyond performing standard communication management, the TMR architecture executes continuous monitor channel comparison and monitor voting logic by cross-referencing outputs across three redundant monitors. If an output variation exceeds the pre-configured percentage limits, the module flags the respective monitor as faulted and logs a distinct entry within the System Event List. While the unit supports vital rack-wide functions, it remains separated from the critical machinery monitoring path, ensuring its operation has no adverse impact on normal, ongoing safety protection loops.

Features

• Monitor Channel Comparison: Dynamically cross-checks and processes diagnostic data from three redundant monitoring cards to maintain TMR system voting integrity.
• Dual Serial Communication: Employs a versatile rear I/O module supporting both RS232 and RS422 protocol media options via an integrated hardware toggle switch.
• Comprehensive Diagnostic LEDs: Provides upfront status visualization via dedicated front-panel indicators for module health, communication activity, Trip Multiply status, and configuration validity.
• Hardware Configuration Keylock: Includes a physical front-panel switch to secure the rack in RUN mode against unauthorized remote or local modification, or enable changes via PROGRAM mode.
• System Contact Inputs: Incorporates discrete dry contact inputs to handle systemic controls including remote alarm inhibit, rack reset, and Trip Multiply triggering.

Applications

• Triple Modular Redundant (TMR) safety and machinery protection layouts.
• Continuous condition monitoring and diagnostic data routing for critical industrial rotating assets.
• Distributed multi-rack turbomachinery instrumentation networks requiring daisy-chained serial host interfaces.

Ordering Information

Note: The individual component spare part number representing the TMR Rack Interface Module main card is 125744-01.

Technical Specifications

Installation Guidelines

• Slot Assignment: Mount the primary processor card strictly into Slot 1 on the far left side of the front chassis, directly adjacent to the system power supply modules.
• Rear I/O Alignment: Install the corresponding RS232/RS422 I/O module into the matching full-height rear slot directly behind the front processor module.
• Protocol Selection: Set the onboard rear slide switch to either the RS232 position or RS422 position based on the physical interface configuration of your host computer or converter.
• Rack Addressing: Utilize the integrated hardware address switch to define a unique tracking identification code for the chassis when deploying multiple racks in a network loop.
• Wiring Extensions: Do not exceed 30 metres for RS232 connections or 1200 metres for RS422 connections to avoid serial data packet loss or signaling degradation.

FAQ

What is the functional difference between a standard RIM and a TMR RIM?

The standard version handles configuration and communication routing for standard racks. The TMR variant adds specific hardware comparison algorithms that continually evaluate outputs from three distinct monitors to implement fault voting logic.

Will a failure or removal of this module interrupt the active machinery trip protection loop?

No. This module handles rack infrastructure setup, communication, and system-wide logging, but it does not reside within the critical safety monitoring path and has no impact on individual monitor operations.

How can I restrict unauthorized users from altering the machinery protection settings remotely?

Turn the front-panel configuration keylock into the RUN position and remove the physical key. This locks out remote and local programming, preventing modifications to active operational thresholds.