Description

The Triconex AO2841 is a highly reliable, fault-tolerant analog output module designed exclusively for the Tricon and Trident safety instrumented systems (SIS) from Triconex, a foremost brand in critical process safety now under the Emerson umbrella. This module is engineered to provide the final interface between the safety logic solver and analog field actuators in the most demanding safety-critical applications. Its primary function is to convert digital commands from the triple modular redundant (TMR) controllers into precise, isolated 4-20 mA analog signals that operate final elements such as emergency shutdown (ESD) valves, damper controllers, and other critical control devices. The Triconex AO2841 is an integral component in ensuring that safety actions are executed with absolute certainty and precision, thereby protecting human assets, the environment, and multi-billion dollar industrial facilities from catastrophic events.

Built to meet the most rigorous international safety standards, the Triconex AO2841 embodies the core TMR philosophy. It features three independent output channels that vote on the output signal, providing an unparalleled level of fault tolerance and diagnostic coverage. This design ensures that no single point of failure can prevent the system from taking a safe action. The module is designed for hot-swappable replacement, allowing for maintenance and troubleshooting without taking the entire safety system offline, thus supporting maximum plant availability. The robust construction and rigorous manufacturing standards of the Triconex AO2841 make it the trusted choice for executing protective functions in the world’s most hazardous processes.

AO2841 TRICONEX

Technical Specifications

Parameter Name	Parameter Value
Product Model	AO2841
Manufacturer	Triconex (Emerson)
Product Type	TMR Analog Output Module
Number of Channels	4 channels (TMR architecture per channel)
Output Signal	4-20 mA (isolated)
Resolution	16-bit
Accuracy	±0.1% of full scale
Load Capacity	0-900 Ohms
Isolation	1500 Vrms channel-to-channel and field-to-system
Update Time	50 ms per block of 4 channels
Power Consumption	1.2 W per channel
Safety Integrity Level (SIL)	Capable of SIL 3 per IEC 61508
Operating Temperature	-40 to 70 °C (-40 to 158 °F)
Diagnostics	Comprehensive online diagnostics, including open wire detection

Main Features and Advantages

The defining feature of the Triconex AO2841 is its Triple Modular Redundant (TMR) architecture. Each of its four output channels contains three independent circuits. These circuits operate in parallel, and a hardware voter compares the three outputs on every scan, ensuring that a correct signal is always delivered even if a fault occurs in one channel. This provides extremely high availability and eliminates single points of failure, which is the cornerstone of its safety certification. The module offers extensive built-in diagnostics that continuously monitor the health of each output circuit, field wiring, and connected load, instantly detecting and reporting faults such as open circuits or short circuits to the main processor.

Another significant advantage is its hot-swappable capability. The Triconex AO2841 can be safely inserted or removed from a powered-up chassis without requiring a shutdown of the entire Tricon system. This drastically reduces maintenance downtime and simplifies module replacement. The module also provides excellent noise immunity and high galvanic isolation between channels and from the field wiring to the system backplane, protecting the sensitive system electronics from transient spikes and ground loops. The robust design of the Triconex AO2841 ensures long-term reliability and stable performance in electrically noisy and physically harsh industrial environments.

Application Field

The Triconex AO2841 is deployed exclusively in safety-critical applications where failure is not an option. Its primary domain is in the Oil & Gas industry, where it is a fundamental component of Emergency Shutdown (ESD) systems on offshore platforms, floating production vessels, LNG terminals, and pipelines. Here, it is responsible for controlling valves that must isolate sections of the process in the event of a detected hazard. Similarly, in gas compression and pump stations, the Triconex AO2841 module acts upon the safety controller’s decision to shut down equipment and prevent catastrophic mechanical failure or rupture.

In the Petrochemical and Chemical processing industries, the module is used within Burner Management Systems (BMS) to safely control fuel valves and within Fire & Gas (F&G) systems to activate suppression systems. Power Generation plants utilize the Triconex AO2841 for turbine overspeed protection and other critical machinery safeguards. In essence, the Triconex AO2841 is specified wherever there is a requirement for a highly reliable, fault-tolerant analog output within a certified safety instrumented system (SIS) to mitigate risk and protect people, assets, and the environment.

AO2841 TRICONEX

Related Products

Triconex AI3351: A TMR analog input module used for reading signals from critical field transmitters within the same safety system.

Triconex DI3401: A TMR digital input module for reading status from safety switches and initiators.

Triconex DO3421: A TMR digital output module for operating solenoid valves and other on/off safety devices.

Triconex MP3008: A main processor module for the Tricon system, which commands the AO2841 module.

Triconex NCM11: A network communication module for integrating the Tricon system with DCS and other networks.

Triconex PWR8352: A redundant power supply module that provides power to the chassis housing the AO2841.

Emerson TxS I/O: A newer generation of safety I/O modules that can interface with legacy Tricon systems.