Triconex 3805H Analog Output Module 8-Channel TMR

Product Overview

The Triconex 3805H acts as a critical execution component within the Tricon Triple Modular Redundant (TMR) safety platform. This high-availability Analog Output (AO) module translates digital commands into precise 4-20mA signals to drive final control elements such as valves and actuators. By utilizing three isolated internal channels, the 3805H ensures continuous operation even if a hardware fault occurs, making it the industry standard for Safety Instrumented Systems (SIS) and critical process control.

Technical Specifications

The 3805H delivers high-precision current loops designed for rugged industrial deployment:

• Output Points: 8 redundant output channels

• Current Range: 4–20 mA (supports +6% overrange up to 21.2 mA)

• Architecture: Triple Modular Redundant (TMR), DC Coupled

• Resolution: 12 bits

• Output Accuracy: <0.25% of FSR (0-21.2 mA) across 0° to 60° C

• Safety Rating: IEC 61508 SIL3 Certified

• Isolation: Full channel-to-channel and bus-to-field isolation

• Diagnostics: Comprehensive microprocessor-controlled fault detection

• Hot-Swap Capability: Supports online replacement without process interruption

Engineering Advantages

• Fault-Tolerant Execution: The TMR architecture executes a 2-out-of-3 voting mechanism directly on the module. This eliminates single points of failure, ensuring your safety valves remain operational during internal component transitions.

• Precision Under Thermal Stress: Most modules drift as cabinets heat up. The 3805H maintains an accuracy of <0.25% FSR even at 140° F (60° C), preventing "nuisance trips" or inaccurate valve positioning in harsh processing units.

• Zero-Downtime Maintenance: The module supports "Hot-Swapping." Maintenance teams replace faulty units while the system remains live, bypassing the need for expensive plant shutdowns to update or repair I/O hardware.

• Robust Diagnostics: Built-in line monitoring identifies field wiring issues and loop integrity faults instantly. The module reports these anomalies to the main processor, allowing for predictive maintenance before a loop fails.

FAQs

• Does the 3805H support 0-20mA signals?The module optimizes for 4-20mA standard loops but provides a full range up to 21.2mA to accommodate overrange requirements and specific signaling needs.

• Can I replace a 3805 (non-H version) with a 3805H?The "H" designation typically indicates high-density or enhanced performance characteristics. In most Tricon racks, the 3805H maintains backward compatibility, but you must verify your specific Chassis version and TriStation 1131 software configuration before installation.

• What condition are these units shipped in?We supply only 100% Brand New and original factory-sealed units. Every module includes a 12-month functional warranty to ensure your SIS remains compliant with safety standards.

• How does the module handle a total loss of communication?The module implements pre-configured fail-safe states. Upon loss of communication with the main processors, the 3805H forces outputs to a user-defined safe value (typically 4mA or 0mA) to ensure the process reaches a secure state.