Yokogawa NFAI841-S50 Analog I/O Module

The Yokogawa NFAI841-S50 Analog I/O Module is a high-performance, safety-rated analog input/output module designed for use within Yokogawa’s ProSafe-RS safety instrumented system (SIS). Engineered to comply with SIL3 standards under IEC 61508, this module supports analog signal monitoring and control in mission-critical applications such as oil & gas, chemical, power generation, and other industrial process systems.

The NFAI841-S50 features 8 isolated analog input channels and 4 analog output channels, with support for HART communication, ensuring smart signal processing and device diagnostics. Its rugged design and advanced fault detection capability provide maximum safety, reliability, and ease of integration into Field Control Station (FCS) environments.

This module enables real-time data acquisition, analog signal control, and secure transmission, making it ideal for systems that require high integrity and performance in both input and output operations.

Product Specifications

Product Applications

The Yokogawa NFAI841-S50 is highly suited for applications requiring a blend of input monitoring and output control in harsh and safety-critical environments:

• Oil & Gas Platforms

  Used in upstream wellhead control and downstream refining operations to monitor and regulate flow, pressure, and temperature signals.

• Chemical and Petrochemical Plants

  Ensures safe chemical reactions by precisely controlling and monitoring analog signals in reactors and batch processes.

• Power Plants (Nuclear, Thermal, Hydro)

  Integrated into turbine control and boiler management systems requiring high-reliability analog data transmission.

• Water and Wastewater Treatment

  Manages chemical dosing, flow monitoring, and feedback-based control in municipal and industrial treatment systems.

• Pharmaceutical Industry

  Enables real-time analog feedback loops for temperature, pH, and pressure control under regulated GxP conditions.

• Food & Beverage Automation

  Helps maintain consistent product quality by managing analog-controlled devices in mixing, heating, and filling stations.

Product Advantages

• Dual Analog Capabilities (Input + Output)

  Reduces hardware footprint by combining I/O functions into a single safety-rated module.

• SIL3 Certified for Safety

  Complies with IEC 61508 to meet the most demanding process safety requirements.

• Integrated HART Communication

  Allows for remote calibration, diagnostics, and enhanced device configuration.

• High Signal Accuracy

  16-bit resolution on both A/D and D/A converters ensures accurate signal processing.

• Robust Channel Isolation

  Each channel is independently isolated, minimizing crosstalk and improving system stability.

• Compact and Modular

  Slim design helps reduce panel space while offering modular expansion capability.

• Diagnostic and Fault Detection

  Includes built-in features for loop monitoring, wire-break detection, and output feedback verification.

• Broad Environmental Tolerance

  Operates in extreme industrial conditions without performance degradation.

Frequently Asked Questions (FAQ)

1. What functions does the NFAI841-S50 support?

   It provides 8 analog input channels and 4 analog output channels in one module.

2. Is this module suitable for use in SIL3 applications?

   Yes, it is certified to SIL3 under IEC 61508.

3. What types of analog signals are compatible?

   It supports standard 4–20 mA, 1–5 V, and 0–10 V signals for both input and output.

4. Does this module support HART communication?

   Yes, it supports both HART 5 and HART 7 for smart device integration.

5. Can the module be mounted on a DIN rail?

   Yes, it is designed for DIN rail or panel mounting via the baseplate system.

6. Is each channel isolated?

   Yes, channel-to-channel and channel-to-ground isolation is provided for both input and output.

7. What control platforms is this module compatible with?

   It is compatible with Yokogawa ProSafe-RS and CENTUM VP systems.

8. What is the resolution of the A/D and D/A converters?

   Both converters operate at a 16-bit resolution for precision.

9. Does the module provide diagnostics or fault detection?

   Yes, it includes loop integrity checks, wire break detection, and output loop monitoring.

10. Can this module function in outdoor or extreme environments?

    Yes, it supports operation from -20°C to +70°C and high humidity conditions.