Description

HIMA X-AI3251 — High-Precision Analog Input Module for SIL 3 Safety Instrumented Systems

Product Overview

Technical Specifications

• Brand: HIMA
• Model: X-AI3251
• Product Type: High-Precision Analog Input Module (Safety-Related)
• Compatible Systems: HIMA HiQuad X, HiDCP X, HiPROM X safety controllers
• Functional Safety Rating: SIL 3 (per IEC 61508), SIL 3 (per IEC 61511)
• Operating Voltage: 24 VDC (±10%)
• Operating Temperature Range: -20°C to +60°C (-4°F to 140°F)
• Relative Humidity: 5% to 95% (non-condensing)
• Analog Input Configuration:
  • Channel Count: 8 independent differential channels
  • Signal Types: 4-20mA, 0-10V, thermocouples (K/J/T/E/R/S/B/N), resistance thermometers (Pt100/Pt1000, Ni100/Ni1000)
  • Measurement Precision: ±0.01% FS (full scale)
  • Resolution: 24-bit
  • Sampling Rate: Up to 100 Hz per channel (configurable)
• Isolation: Channel-to-channel, channel-to-power, and channel-to-backplane isolation (500VAC, 1 minute)
• Fault Detection:
  • Open-Circuit Detection (for 4-20mA signals)
  • Short-Circuit Detection
  • Overrange/Underrange Detection
  • Internal Self-Diagnosis (continuous monitoring of module electronics)
• Communication Interface: HIMA Safety Bus (seamless integration with safety controllers)
• Protection Rating: IP20 (for cabinet mounting)
• Mounting Type: DIN rail mounting (35mm standard)
• Weight: Approximately 0.9kg (1.98lbs)
• Warranty Period: 3 years

Core Advantages

1. SIL 3 Safety Compliance: The X-AI3251 is certified for SIL 3 applications, meeting the highest functional safety requirements for critical industrial processes. Continuous self-diagnosis and fault detection mechanisms minimize the risk of undetected failures, ensuring safe system operation.
2. Ultra-High Measurement Precision: Equipped with 24-bit ADCs and advanced signal conditioning technology, the X-AI3251 delivers ±0.01% FS precision—enabling accurate monitoring of even the smallest process variations, which is critical for safety interlock activation.
3. Multi-Signal Compatibility: Supports a wide range of analog signals (current, voltage, thermocouples, RTDs) without the need for additional adapters, reducing system complexity and component costs.
4. Robust Isolation & Noise Immunity: 500VAC isolation between channels and power, combined with EMC-optimized design, ensures reliable operation in noisy industrial environments and protects against voltage transients.
5. Seamless HIMA Integration: Designed exclusively for HIMA’s safety controllers, the X-AI3251 integrates via the HIMA Safety Bus, supporting plug-and-play configuration and automatic parameter synchronization—simplifying installation and commissioning.
6. Durable Industrial Design: Built to withstand extreme temperatures (-20°C to +60°C) and harsh process environments, the X-AI3251 delivers long-term reliability with minimal maintenance.

Application Scenarios

• Oil & Gas Industry: Used in refineries, offshore platforms, and pipelines to monitor pressure, temperature, and flow in safety-critical systems (e.g., reactor vessels, pipeline shutdown systems).
• Chemical Industry: Applied in batch and continuous processes to track temperature, pressure, and level of hazardous materials, enabling safe shutdowns in case of process deviations.
• Power Generation: Integrated into thermal, nuclear, and renewable energy plants to monitor boiler temperature, steam pressure, and turbine vibrations—supporting safe and efficient power production.
• Pharmaceutical Industry: Used in GMP-compliant manufacturing processes to monitor temperature and pressure in reactors and storage vessels, ensuring product quality and process safety.
• Food & Beverage Industry: Applied in pasteurization and sterilization processes to monitor temperature and flow, ensuring compliance with food safety regulations and preventing process failures.

Competitor Comparison

Selection & Usage Recommendations

1. Safety Compliance Verification: Ensure the X-AI3251 aligns with your system’s SIL requirements (up to SIL 3) and industry standards (IEC 61508/IEC 61511) for critical process control.
2. Signal Compatibility Check: Confirm the module supports your specific sensor signals (e.g., 4-20mA transmitters, Pt100 RTDs) to avoid the need for additional signal converters.
3. Installation Best Practices: Mount the X-AI3251 in a well-ventilated cabinet away from heat sources and high-voltage equipment. Use shielded twisted-pair cables for sensor wiring, with shield layers grounded at one end to minimize noise.
4. Configuration Guidelines: Use HIMA’s HIMatrix Configurator software to configure signal types, sampling rates, and fault detection parameters. Calibrate the module periodically (per HIMA’s recommendations) to maintain measurement accuracy.
5. Troubleshooting: Leverage the module’s built-in fault detection and status LEDs to quickly identify issues (e.g., open circuits, short circuits). For complex problems, contact HIMA’s authorized service team—do not modify or disassemble the module, as this may void safety certifications.
6. System Expansion: To increase analog input capacity, multiple X-AI3251 modules can be daisy-chained via the HIMA Safety Bus, supporting scalable SIS designs without compromising performance or safety.