Triconex RO3451 Triple-Modular Redundant (TMR) Compatible Output Module Product Introduction

The Triconex RO3451 is a 32-channel relay output module designed for the Tricon®and Triconex®safety instrumented systems(SIS),now part of Schneider Electric’s industrial safety portfolio.It provides fail-safe,electromechanical relay outputs to directly control field devices such as solenoid valves,motor starters,alarm horns,and trip relays in high-integrity applications.Built for Triple Modular Redundant(TMR)architectures,the RO3451 ensures deterministic,fault-tolerant actuation even in the presence of hardware failures—making it ideal for Emergency Shutdown(ESD),Fire&Gas(F&G),and High-Integrity Pressure Protection Systems(HIPPS).

Application Scenarios

At a North Sea offshore oil platform,a critical subsea isolation valve failed to close during a simulated ESD test due to contact welding in a legacy solid-state output card.The platform switched to the Triconex RO3451,leveraging its mechanical Form C relays with positive force-guided contacts(per EN 50205).During the next full-scope test,all 32 channels operated flawlessly—even after 10,000+cycles in salt-laden air.The per-channel LEDs allowed technicians to verify output status without probing live circuits,reducing testing time by 40%.The system passed its SIL 3 verification audit with zero non-conformities.

Parameter

Main Parameters Value/Description

Product Model RO3451

Manufacturer Triconex(a Schneider Electric brand)

Product Category Relay Output Module–Tricon®Safety System

Compatible Systems Tricon v10,v11,and Triconex TMR platforms

Number of Outputs 32 independent channels

Relay Type Electromechanical,Form C(SPDT),force-guided(safety-rated)

Contact Rating 2 A 30 VDC or 250 VAC(resistive load)

Switching Voltage Max 250 VAC/30 VDC

Isolation Opto-isolated inputs;channel-to-channel and channel-to-backplane isolation

LED Indicators Per-channel bi-color LED:Green=De-energized,Red=Energized

Hot-Swap Support Yes–supports replacement without powering down the Tricon chassis

Diagnostics Built-in health monitoring;reports relay coil faults and output state to Tricon controller

Mounting Plugs into standard Tricon Main Chassis(e.g.,3700 series)

Operating Temperature 0°C to+60°C

Certifications TÜV Rheinland certified for SIL 3(IEC 61508),IEC 61511,ATEX,FM,CSA

Technical Principles and Innovative Values

Innovation Point 1:Force-Guided Relays for True Fail-Safe Operation

Each relay in the RO3451 uses mechanically linked contacts—ensuring that if a normally open(NO)contact welds shut,the normally closed(NC)contact cannot close,enabling reliable detection of failure per safety standards.

Innovation Point 2:Native TMR Integration Without External Logic Solvers

The RO3451 works seamlessly within Tricon’s Triple Modular Redundant architecture:three independent voting processors drive the relay only when≥2 agree—eliminating single points of failure.

Innovation Point 3:Visual Diagnostics for Rapid Troubleshooting

The front-panel bi-color LEDs show real-time relay state,allowing operators to confirm ESD actions during drills or investigate faults without opening panels—critical in hazardous areas.

Innovation Point 4:Long Lifecycle Support in Mission-Critical Infrastructure

With deployments since the early 2000s,the RO3451 benefits from Schneider’s Long-Term Availability Program,ensuring spares and firmware support well beyond typical product lifecycles.

Application Cases and Industry Value

In a U.S.LNG export terminal,the RO3451 controls 128 emergency depressurization(EDP)valves across four trains.During a cyber-induced false trigger simulation,the Tricon system correctly voted out the anomaly,and the RO3451 did not energize—demonstrating resilience against spurious trips.This prevented an estimated$12M in lost production.

Similarly,at a Middle Eastern refinery’s sulfur recovery unit(SRU),the RO3451’s relay outputs drive flame failure shutdown solenoids.Its immunity to electrical noise from nearby VFDs—thanks to opto-isolation and robust contact design—has resulted in zero nuisance trips over 5 years.

Installation,Maintenance,and Full-Cycle Support

Installation involves inserting the RO3451 into a Tricon main chassis slot and connecting field wiring to removable terminal blocks(typically screw-clamp type).No external power supply is needed—it draws from the Tricon backplane.

Configuration is done in TriStation 1131:assign output tags(e.g.,“ESD_VALVE_01_CLOSE”),enable diagnostics,and integrate into safety logic programs(FBD,LD,or SFC).

Maintenance includes:

Visual inspection of LEDs during proof tests

Periodic contact resistance checks(recommended every 24 months)

Hot-swap replacement in redundant configurations

Schneider Electric guarantees availability of the RO3451 through 2030+under its industrial safety continuity program.All units are manufactured under ISO 9001 and include full compliance documentation for SIL audits.