Component Snapshot At-a-Glance

• Model: 8111N
• Alt. P/N: Base standard 8111; suffix N = full PCB conformal coated harsh offshore variant
• Product Series: Triconex Tricon Triple Modular Redundant (TMR) Safety Instrumented System (SIS)
• Hardware Type: 19-inch 4U high-density expansion chassis with integrated TriBus backplane
• Key Feature: 16 universal module slots, redundant power/fan bays, fully coated backplane circuit board for salt fog & chemical vapor corrosion resistance
• Primary Field Use: Extends main Tricon controller rack capacity; houses TMR CPU, analog/digital I/O, communication modules for large-scale ESD, F&G safety loops.

Hard-Numbers: Technical Specifications

• Protocol Support: Proprietary 25Mbps TriBus synchronous rack backplane bus
• Slot Count: 16 full-height module slots; dual power supply slots (fits PS8310/8310N2) + dual redundant cooling fan bays
• Backplane Data Rate: 25Mbps synchronous inter-module TMR communication
• Operating Temperature: 0°C to +60°C operational; -40°C to +85°C storage
• Isolation Rating: 1500VAC galvanic isolation between power rails and TriBus signal traces
• Total Max Backplane Load: 350W combined supported output from dual redundant PS8310 power supplies
• Cooling: Dual redundant hot-swap cooling fans with fan fault alarm contacts
• Alarm Output: Rear terminal block SPDT chassis fault relay (power/fan/temp fault signaling to DCS)
• Hot-Swap Compatibility: All installed CPU/I/O/TCM modules support live replacement without rack shutdown
• Coating Grade: Full PCB conformal coating for offshore marine salt fog, coastal refinery corrosive atmosphere
• Certifications: IEC 61508 SIL3, ATEX Zone 2, UL, CE, ISA-84
• Mounting: Standard 19-inch EIA rackmount or panel mount
• Dimensions (H×W×D): 178mm × 483mm × 292mm
• Weight (Empty Chassis): 10.2kg

The Real-World Problem It Solves

Uncoated base 8111 bare backplane suffers rapid trace corrosion in offshore FPSO, coastal refinery salt fog environments. Smaller 8-slot racks lack capacity for large ESD systems with dozens of TMR I/O and communication cards. Single fan/power layouts create full chassis shutdown single-point failures violating SIL3 safety compliance.Where you’ll typically find it:

• Refinery reactor, distillation unit large-scale ESD safety instrumented racks
• Offshore drilling rig & FPSO fire/gas (F&G) high channel count safety control cabinets
• Fossil power plant boiler, turbine burner management SIL3 extended I/O systems

This high-density coated expansion chassis doubles available module slots, adds redundant cooling and power infrastructure, and resists corrosive plant air to extend service life in harsh industrial sites.

Hardware Architecture & Under-the-Hood Logic

Passive multi-layer gold-plated TriBus backplane chassis; no onboard CPU, acts as shared power and TMR communication backbone for all plug-in Tricon modules.

1. Dual PS8310/8310N2 power supplies feed parallel redundant 6.5VDC power rails across all 16 module slots.
2. Multi-layer backplane separates low-voltage TriBus signal traces and high-current power layers to minimize EMI crosstalk.
3. Dual independent cooling fans run load-sharing; single fan loss triggers chassis fault alarm without rack shutdown.
4. Gold-plated edge slot connectors prevent oxidation in high-humidity cabinets, maintain stable low-impedance module contact.
5. TriBus backplane synchronizes 2oo3 hardware voting data between all TMR CPU, I/O and communication modules.
6. Full conformal coating fully encapsulates all backplane PCB traces, connectors and passive components to block salt dust, moisture and chemical vapor corrosion.
7. Rear terminal block hardwired fault relay signals chassis power, fan, overtemperature faults to plant DCS/operator HMI.

Field Service Pitfalls: What Rookies Get Wrong

Single power supply installation without redundant second PS8310N2Techs install only one power module to save rack space. Single supply setup creates unmitigated single-point failure, invalidating SIL3 safety certification for the entire expansion chassis.

• Field Rule: All SIL3 safety 8111N racks require two matched 8310N2 power supplies in parallel redundant configuration.

Blocking front/rear ventilation with dense cable bundlesOver-stuffing rear TA terminal wiring blocks chassis airflow and fan intake. Internal heat pushes operating temperature above 60°C, triggering persistent chassis fault alarms and TriBus communication timeouts.

• Quick Fix: Maintain minimum 30mm clearance front and rear of chassis; separate power cable looms and signal wiring trays.

Mismatched standard uncoated modules into N-series coated chassisMixing uncoated 3008 / 3501 / 4352A standard modules inside 8111N harsh environment rack creates uneven corrosion rates and premature module failure.

• Field Rule: All modules deployed inside 8111N offshore chassis must be N / N2 conformal coated variants only.

Commercial Availability & Pricing Note

Please note: The listed price is for reference only and is not binding. Final pricing and terms are subject to negotiation based on current market conditions and availability.