Description
The Triconex 3623T is a TMR (Triple Modular Redundant) Digital Output (DO) module designed for use in Tricon Safety Instrumented Systems (SIS). This module features 16 isolated output channels and is engineered for high-integrity applications such as Emergency Shutdown (ESD), Fire and Gas (F&G) systems, and Burner Management Systems (BMS). The “T” suffix denotes External Termination compatibility, meaning the module interfaces with field wiring via an external termination panel (ETP) rather than direct front-panel wiring.
Commercial Availability & Lifecycle Status
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Condition: New Original (Factory Sealed) or Refurbished (Tested)
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Availability: Critical Spare Part; typically stocked by specialist safety system suppliers.
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Standard Lead Time: 1–3 business days.
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Warranty: 12-Month Warranty.
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Pricing Note: Safety-critical modules are subject to fluctuating market availability. Contact us for a firm quote and to verify current firmware compatibility.
Technical Specifications
| Parameter | Value |
| Manufacturer | Schneider Electric (Triconex) |
| Model Number | 3623T |
| Architecture | TMR (Triple Modular Redundant) |
| Number of Channels | 16, Isolated |
| Output Type | Discrete, Supervised |
| Nominal Voltage | 24 V DC |
| Output Voltage Range | 18 to 30 V DC |
| Maximum Load Current | 2.0 A (Peak), 1.7 A (Continuous at 45°C) |
| Minimum Load | 10 mA (required for valid load supervision) |
| Leakage Current | < 2.0 mA |
| Isolation | 1,500 V DC (Channel-to-Channel / Channel-to-Logic) |
| Self-Test Interval | Comprehensive background testing every 10 ms |
Technical Design & Safety Integrity
Triple Modular Redundancy (TMR)
The 3623T utilizes the patented Triconex TMR architecture. Each of the 16 channels contains three independent output sub-circuits. A physical “voting” mechanism on the module determines the final state of the output. If one branch of the three fails, the other two maintain the correct state (2-out-of-3 voting), ensuring the safety function remains available without triggering a nuisance trip.
Output Supervision (Line Monitoring)
This module is “Supervised,” meaning it continuously monitors the health of the field wiring and the load.
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Short Circuit Detection: Protects the module from high-current faults.
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Open Circuit Detection: Detects if a solenoid or relay coil has become disconnected (requires a minimum 10 mA load).
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Stuck-On/Stuck-Off Detection: Internal circuitry verifies that the output switch is actually following the command from the main processors.
External Termination (3623T vs. 3623)
The 3623T requires a specialized interface cable (typically the 175x or 179x series) to connect to an External Termination Panel (ETP). This setup is preferred in large-scale industrial plants because it allows for:
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Simplified field wiring landing.
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Fused protection per channel on the ETP.
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Interposing relays to be mounted externally if the load exceeds 2.0 A.
Field Implementation & Maintenance FAQ
What happens if the “Pass” LED goes out?
A dark “Pass” LED indicates that the module has failed its internal self-diagnostics. Because the system is TMR, the process will likely continue to run using the remaining healthy redundant branches, but the module should be replaced immediately to restore fault tolerance.
Can I hot-swap the 3623T?
Yes, the 3623T is designed for “Hot Replacement.” You can pull a faulty module from the chassis and insert a new one while the system is powered and the process is running. The new module will automatically run a self-test, synchronize its state with the active processors, and take over its share of the load.
Why is the module reporting a “Load Alarm”?
A Load Alarm occurs if the field circuit is drawing less than 10 mA or if there is a high-resistance connection in the field. This is common when driving high-impedance electronic inputs rather than physical solenoids. In such cases, a “dummy load” resistor may be required across the field terminals to satisfy the supervision circuit.
Does it support SIL 3 applications?
Yes. When installed as part of a correctly configured Tricon system (v9.6 or later), the 3623T is suitable for use in Safety Integrity Level 3 (SIL 3) applications as defined by IEC 61508.
Do you need the specific pinout for the External Termination Panel, or are you looking for the compatible interface cable part number (e.g., 1751, 1752) for this module?
