T8471C output module

T8471C digital output module
Product Overview
T8471C is a Trusted TMR 120VDC digital output module produced by ICS TRIPLEX (now Schneider Electric/Emerson) in the United States. It is a core I/O component of the Trusted 8000 series Safety Critical Control Systems (SIS) and is widely used in high-risk industrial scenarios such as petrochemicals, power, and metallurgy.

📌 T8471 is a 120VDC output version, T8472 is a 120VAC output version, and T8473 is a 120VAC isolated output version. The suffix C usually indicates a specific revision or configuration.

Model Interpretation
Meaning of field codes
T-Trusted Series (Triple Modular Redundant Security System)
84- Digital output module class
71-120VDC digital output (72=120VAC, 73=120VAC isolated)
C – Version/Revision Level
Core technical parameters
Parameter specifications
Brand ICS TRIPLEX (Schneider Electric/Emerson)
Belonging to the Trusted 8000 series TMR security control system
Module Type Digital Output (DO)
Output voltage 120VDC
32 channels (TMR triple redundancy)
Output type: Transistor Output
Fault tolerant architecture TMR (Triple Modular Redundancy), 2-out-of-3 voting mechanism
Safety level SIL 3 (IEC 61508)/Cat. 4 (EN 954-1)/PL e (ISO 13849-1)
Response time ≤ 1ms (typical)
Working voltage 24VDC (module power supply)
Working temperature -20 ° C~+70 ° C
Storage temperature -40 ° C~+85 ° C
Humidity 5%~95% RH (non condensing)
Protection level IP20 (installed inside the cabinet)
Installation method: DIN rail/chassis slot (SmartSlot)
hot-swapping ✅ Support online replacement (RIOP)
self-diagnosis ✅ Hardware level self diagnosis+SOE event recording (1ms accuracy)
Programming software IEC 61131 TOOLSET (Trusted Toolset)
System architecture and working principle
┌──────────────────────────────────────────────────────────┐
│ Trusted 8000 TMR Security Control System │
│ │
│——————— TMR bus ┌———————– │
│ │ T8110B/ │◄══════════════►│ T8471C │ │
││ T8111C │ (Triple Redundancy) │ 120VDC Digital Output ││
││ Security Processor ││· 32 Channel DO ││
│└—————- ┘│· TMR Voting Output ││
│ │ └───────┬──────────┘ │
││ Given/Feedback │ 120VDC Output │
│ ▼ ▼ │
│ ┌─────────────┐ ┌──────────────────┐ │
││ Upper system ││ On site actuators ││
││ (DCS/SIS) ││· Electromagnetic valve ││
│└——————- ┘│· Relay ││
││· Contactor coil ││
│ └──────────────────┘ │
└──────────────────────────────────────────────────────────┘
TMR Triple Redundancy Working Principle
Stage description
Three parallel channels with three independent output channels simultaneously receive the same control instructions
Real time voting 2-out-of-3 voting mechanism, automatically blocking any channel failure
Fault isolation module level fault detection+isolation, the fault does not propagate to the system output
When switching to a single point of failure without disturbance, the system continues to operate without interruption in output
SOE records 1ms precision event sequence with timestamp
core advantage
Advantages Explanation
🔒 SIL 3 safety level meets the highest functional safety requirements and is suitable for critical circuits such as ESD emergency shutdown
⚡ TMR triple redundant hardware level fault tolerance, automatic shielding of single point failures, and non-stop system operation
🔌 hot-swapping ✅ Replace modules online without stopping the machine
📊 1ms SOE event sequence recording accuracy of 1ms, convenient for accident analysis
🛡️ Fault self diagnosis hardware+software regular self check, quickly locate faulty modules
🌡️ Wide temperature operation -20 ° C~+70 ° C, suitable for harsh industrial environments
🔄 120VDC output is suitable for on-site equipment such as high-power solenoid valves and contactors
Typical application scenarios
Industry Applications
⚡ Emergency shutdown of power turbine ESD, generator protection, and switching of plant power
🛢️ Petrochemical reactor safety interlock, ESD emergency shutdown, flare system control
🏭 Chemical hazardous process safety protection, toxic gas interlocking
🔧 Metallurgical blast furnace/converter safety protection, cooling water system monitoring
💧 Safety control of large-scale water pumping stations
Constant pairing module (Trusted 8000 ecosystem)
Module Model Type Channel Number Description
T811B/T8111C TMR Security Processor – ⭐ System Core
T8403C TMR digital input (DI) 40 channel 24VDC
T8431C TMR Analog Input (AI) 40 Channels ⭐ Frequent pairing
T8480C TMR Analog Output (AO) 40 Channels ⭐ Frequent pairing
T8451C TMR digital output (DO) 40 channel 24VDC
T8461C TMR digital output (DO) 40 channel 24/48VDC
⭐ T8471C TMR digital output (DO) 32 channel 120VDC (this product)
T8472C TMR digital output (DO) 32 channel 120VAC
T8473C TMR Digital Output (DO) 32 Channel 120VAC Isolation
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T8100C Controller Case 10 Slot Host Box
T8300 Expansion Chassis – Remote I/O Expansion