Description
Designed for deployment within the high-availability Trusted Safety Platform, this module provides 32 individually isolated, sourcing digital output channels. The “C” suffix typically denotes a conformally coated assembly, which guards internal component circuitry against corrosive atmospheric gases and moisture common in petrochemical, refining, and subsea power distribution controls. It operates via a hardware-voted fault-tolerant architecture (RunSafe 3-3-2-0) to prevent both fail-to-function events and spurious trips in IEC 61508 SIL 3 safety instrumented systems (SIS).
Technical Specifications
| Parameter | Specification / Value |
| Brand | ICS Triplex / Rockwell Automation |
| Model / Series | Trusted TMR Safety System |
| Part Number | T8471C |
| Channel Count | 32 sourcing digital output channels (individually isolated) |
| Nominal Output Voltage | 120 V DC |
| Architecture | Triple Modular Redundant (TMR) internal hardware voting |
| Fault Tolerance | RunSafe 3-3-2-0 degradation management |
| Isolation Barrier | 2,500 V impulse withstand opto/galvanic isolation |
| Diagnostic Coverage | Triplicated voting tests for current, voltage, and stuck-on/stuck-off switches |
| Line Monitoring | Per-channel open-circuit and short-circuit field load testing |
| Sequence of Events (SOE) | Time-stamped event reporting with 1 ms resolution |
| Coating Type | Conformal coating for harsh environments (Class G3 compliance) |
Field Application and System Integration Notes
Diagnostic Testing and Over-Current Management
The T8471C carries out continuous, automated self-tests on each output circuit to verify switching element health.
- Stuck-On/Off Monitoring: The module periodically pulses output circuits at ultra-high speed to verify element switching responsiveness without dropping the field load or causing process actuators to shift.
- Fuse-less Protection: It features integrated electronic over-current protection per channel. If a short-circuit occurs on the field wiring side, the channel dynamically limits the current profile, issues a specific diagnostic alarm over the system backplane, and logs the event to the SOE buffer.
Smart Line Monitoring Configurations
To effectively track line status and bypass false diagnostics, the module must detect a nominal current footprint.
- Field Loading: If connected to a field device that draws minimal current (such as a high-impedance relay coil or digital interposing card input), the front panel status LED will flash green to signal “field load missing or too small.”
- Resolution: Install an appropriately sized bleed resistor or dummy load at the Field Termination Assembly (FTA) terminal housing if your field element fails to meet the minimum required operational current draw specified in the Trusted system architecture manual.
Hot-Replacement Constraints
The module supports on-line hot-swapping using a dedicated companion slot pairing arrangement.
- Before extracting a faulted T8471C module from the active chassis, ensure the adjacent companion slot houses a verified, healthy module in a standby or “educated” operational state.
- Pulling the module without completing the software-driven interlock handshake can trip the local backplane segment into a hardware-fault shutdown state.
Commercial and Procurement Data
- Product Condition: New Original (Conformally Coated, Factory Sealed) or Refurbished/Tested Surplus.
- Standard Warranty: 12-month complete component-level exchange warranty.
- Estimated Lead Time: Departs international logistics hubs within 2 to 4 business days for in-stock parts.
- Pricing Notice: Prices fluctuate based on hardware lifecycle positioning, structural component availability, and specific regional safety certification validation requests. Contact our sales desk for an official, itemized commercial quote.
