Product Overview

The 3805H is a high-integrity Analog Output Module engineered for the Tricon Triple Modular Redundant (TMR) safety platform. Specifically designed to drive critical final control elements, this 8-channel module provides precise 4-20mA current signals required for modulating valves, actuators, and other variable process controllers. By utilizing TMR architecture, the 3805H processes data through three independent paths and employs hardware voting logic to ensure that a single component failure does not disrupt the output signal. This fault-tolerant design is essential for Safety Instrumented Systems (SIS) that must adhere to SIL3 standards, ensuring that mission-critical processes remain under total control even during hardware degradation.

Critical Engineering Specs and Performance Profiles

The 3805H module is built to maintain signal purity and system availability in high-consequence industrial environments:

• Signal Fidelity: Features 12-bit resolution across a 0 to 21.2mA range, ensuring granular control for sensitive process adjustments.

• Accuracy Threshold: Maintains a precision of less than 0.25% of Full Scale Range (FSR), providing consistent performance across the entire 4-20mA spectrum.

• TMR Architecture: Triple-redundant, DC-coupled current loops ensure that the safety loop remains closed and operational during individual channel faults.

• Thermal Endurance: Engineered for extreme reliability, capable of operating in ambient temperatures ranging from -40°C to +70°C.

• Isolation and Calibration: Each of the 8 channels features independent isolation, preventing fault propagation between different field devices.

• Physical Construction: A heavy-duty industrial unit weighing 2.75kg with standardized dimensions of 49 x 45.3 x 6.8 cm for Tricon rack integration.

• Overrange Capacity: Includes a +6% overrange capability (up to 21.2mA) to allow for sensor saturation and control headroom.

Primary Industrial Roles and Deployment

The Triconex 3805H is a fundamental component for facilities where unplanned downtime or control loss poses significant risk: