TRICONEX 3805E Analog Output Module

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Technical Brief: TRICONEX 3805E 8-Channel SIL-3 Analog Output Module

Product Positioning
3805E is an 8-channel, triple-modular-redundant (TMR) analog output card for Tricon v9/v10/v11 systems.

It converts the voted digital control word into 4–20 mA or 0–10 V signals that drive actuators, valves, or variable-speed drives with fault-tolerant accuracy and sub-millisecond response.

Core Specifications
• Channels: 8 isolated outputs (software-selectable 4–20 mA / 0–10 V)
• Output Accuracy: ±0.1 % F.S. over –40 °C … +70 °C
• Resolution: 12-bit; over-range to +6 % (0–21.2 mA)
• Response Time: ≤ 3 ms command-to-output
• Load Drive: 0–750 Ω current, ≥ 2 kΩ voltage
• Isolation: 2.5 kV impulse, 250 V working channel-to-channel & channel-to-bus
• Diagnostics: Open-loop, short-circuit, over-range, watchdog fault detection
• Hot-swap: Supported without rack shutdown

Typical Applications
• Emergency shutdown (ESD) valve control in LNG terminals
• Furnace fuel-gas modulation in petrochemical crackers
• Turbine governor set-point generation for power plants

TRICONEX 3805E – Fault-Detection Features (Field Quick-Reference)

 Channel-Level Diagnostics
• Open-loop monitoring – continuously checks loop continuity of 4-20 mA circuits; flags any wire break.
• Short-circuit / overload detection – shuts down the affected channel and sets the Fault LED if output current exceeds 0.5 A or a short is detected.
• Over-range & under-range alarms – triggers when output is > 21.2 mA or < 3.2 mA.
• Relay contact-weld test – for digital-output versions, verifies that relay contacts are not stuck ON or OFF and forces the channel to the safe state when required.

Module-Level Diagnostics
• TMR vote mismatch – if the three processing paths disagree, the faulty path is isolated and operation continues in 2oo3 mode; mismatch code is reported.
• Power & reference monitoring – alarms when 24 V supply or internal 5 V reference deviates more than ±5 %.
• Watch-dog timer – on timeout, outputs drop to zero and the “WDT Trip” bit is set.
• Temperature-drift compensation – internal sensor triggers auto-calibration beyond 0–60 °C and raises a “Temp Cal” advisory in TriStation.

Communication & Logging
• TriBus diagnostic codes – all faults are transmitted in real time via 20 Mbps TriBus to the main processor and displayed in TriStation 1131 or the SOE.
• LED indicators – PASS, FAULT, ACTIVE, TX/RX for immediate fault localization.
• 1 ms SOE time-stamping for post-incident analysis.

Maintenance-Friendly Features
• Online self-test – a 100 ms test sequence can be triggered manually or automatically to verify the analog output path without disturbing the process.
• Hot-swap capability – faulty channels or the entire module can be replaced on-line; the system automatically synchronizes redundant data with no process upset.

Ordering Information & Related TRICONEX Part Numbers