Product Overview

The Schneider Electric 3805H is an 8-channel high-density Analog Output (AO) module designed for Tricon™ v9/v10/v11 safety systems. Engineered for critical process control, it provides reliable 4–20 mA or 0–10 V outputs to field devices such as valves and actuators. Built with Triple Modular Redundancy (TMR), the module ensures continuous operation even in the event of internal faults, making it ideal for high-availability, safety-critical applications. Its robust construction allows operation in harsh industrial environments, while its compact footprint simplifies installation and maintenance.

Key Features

Triple Modular Redundancy (TMR) Design

• Three independent output circuits per channel with hardware voting to maintain accurate signals even during a component failure

• Fault-tolerant operation ensures >99% internal fault coverage and continuous output without process disruption

High Precision and Fast Response

• Output accuracy within ±0.1% of full scale

• Supports 4–20 mA and 0–10 V analog outputs with <1 ms response time

• 12-bit resolution for precise actuator positioning and process control

Robust Diagnostics

• Continuous loop monitoring detects open or short circuits in field wiring

• Internal self-tests validate DAC performance and voting integrity

• LED status indicators provide immediate feedback on module health

Operational Durability

• Rated for extreme temperatures: -40°C to +70°C operating, -40°C to +85°C storage

• MTBF >300,000 hours ensures long-term reliability

• Compact design allows hot-swappable replacement without system downtime

Safety and Compliance

• Conforms to UL, CE, TUV, and ISO standards

• Galvanic isolation protects the system logic from field-side electrical disturbances

Technical Specifications

Applications

• Emergency Shutdown (ESD) systems for critical valve control

• Fire and Gas (F&G) safety systems

• Turbomachinery and large compressor speed/throttle control

• High-availability safety systems requiring precise, redundant analog outputs

Installation Notes

The 3805H is compatible with Tricon™ systems v9/v10/v11 and is commonly paired with an External Termination Panel (ETP) for simplified field wiring and over-current protection. The module supports hot-swappable installation for zero downtime maintenance.

FAQ

Q: Can the 3805H module maintain output during a fault?
A: Yes, its TMR architecture ensures continuous operation and accurate outputs even if one internal leg fails.

Q: What output ranges are supported?
A: Each channel supports both 4–20 mA and 0–10 V analog outputs.

Q: Is the module suitable for extreme environments?
A: Yes, it operates reliably from -40°C to +70°C and can be stored up to +85°C.

Q: Can the module be replaced without shutting down the system?
A: Yes, the 3805H is hot-swappable and automatically synchronizes with the active controllers.