ICS T8191 TMR Shield Communications Module

1. Basic Information

2. Hardware Specifications

1. Power Supply

   ‑ Backplane supply: 20‑32 VDC (nominal 24 VDC), dual redundant backplane power; power consumption approx. 18‑24 W

2. Processor & Memory

   ‑ On‑board TMR 3‑channel co‑processor with hardware 2‑out‑of‑3 voting;

   ‑ On‑board Flash and SDRAM cache for serial protocol processing and IRIG‑B time‑synchronization, interfacing both active and standby processors.

3. Communication Interfaces

   ‑ Backplane: Dual 48‑way DIN41612 connectors for simultaneous connection to active and standby CPUs, no communication break during fail‑over;

   ‑ External: 2 configurable RS422/485 channels (2‑wire /4‑wire); IRIG‑B time‑sync input port;

   ‑ Metallic shield enclosure for enhanced EMC anti‑interference performance.

4. Supported Protocols

   Modbus RTU (Master/Slave), IRIG‑B time‑synchronization protocol, for engineering workstations, third‑party serial devices and external clock sources.

5. Environmental Conditions

   ‑ Operating temperature: ‑40℃ ~ +70℃;

   ‑ IP20 (inside cabinet); full electrical isolation; metallic shield for EMI suppression; relative humidity 5‑95% non‑condensing.

3. Key Functions

1. TMR Triple‑Modular Redundancy, Dual‑CPU simultaneous connection: The module links to both active and standby processors. Serial communication remains intact during CPU switch‑over or maintenance. 3‑channel hardware voting isolates single‑channel faults automatically, supporting hot‑swap online replacement.
2. IRIG‑B high‑precision time synchronization: Receives external clock signal to provide unified timestamp for whole Trusted system, guarantees time consistency for SOE sequence‑of‑event logs.
3. Modbus RTU serial gateway: Realizes bidirectional data exchange between SIS and third‑party serial devices, offloads serial‑communication burden from main CPU.
4. EMC shielding protection: Metallic shield housing ensures stable serial communication under heavy electromagnetic interference.
5. Hardware Self‑diagnosis: Real‑time diagnosis for serial links, channels and clock signals with timestamped fault logging and front‑panel status LEDs.
6. Black‑channel safe communication: Safety channel isolation prevents external serial‑port faults from affecting SIS safety logic.

4. Typical Applications

5. Important Notes

1. Firmware version must strictly match T8110C / T8111C processor firmware. Mismatched firmware causes communication or time‑sync failure. Verify firmware build number for spare‑part replacement.
2. T8191 only supports serial port and IRIG‑B time‑sync, without Ethernet port. Use T8151B for Ethernet communication; they cannot substitute each other.
3. Special installation requirement: it is fitted at rear side of controller chassis, not standard front I/O slots. Not allowed in expansion chassis, only for T8100 main controller chassis.
4. Compatible only with dedicated Trusted chassis; not applicable for standard PLC racks.