SensorsEurope NDIR Gas Sensor Module AGM

Overview

The SensorsEurope NDIR Gas Sensor Module AGM is an OEM-grade, dual-wavelength non-dispersive infrared (NDIR) sensing platform engineered for high-reliability integration into environmental monitoring systems, industrial safety analyzers, and process control instrumentation. Unlike filter-wheel or photoacoustic architectures, the AGM employs a single-beam, solid-state optical path with no moving parts—ensuring mechanical robustness and long-term metrological integrity. Its core measurement principle relies on Beer–Lambert absorption spectroscopy in the mid-infrared range (typically 2–10 µm), where target gases—including carbon monoxide (CO), carbon dioxide (CO₂), methane (CH₄), and nitrous oxide (N₂O)—exhibit distinct, non-overlapping vibrational absorption bands. The dual-wavelength configuration enables active reference compensation, effectively rejecting common-mode drift from dust accumulation, window fouling, or source intensity variation. All optical components—including IR source, interference filters, and pyroelectric detector—are sourced from certified European suppliers and subjected to 100% burn-in and parametric screening under ISO 9001-certified manufacturing protocols.

Key Features

• True single-beam NDIR architecture with dual-wavelength detection for real-time baseline correction and enhanced signal stability
• Integrated Peltier-based temperature stabilization (55 °C ±5 °C) ensuring consistent thermal conditions across the optical cavity—critical for minimizing zero drift in variable ambient environments
• Optional barometric pressure compensation (800–1200 mbar range) with <0.2% FS/10 mbar span error correction, enabling accurate operation at altitude or in pressurized enclosures
• Configurable digital time constants (0.5 s to 20 s) via DIP switches—allowing developers to balance response speed against noise rejection per application requirements
• Multi-format analog outputs (4–20 mA, 0–10 VDC, etc.) with 10-bit linearity and RS232 digital interface (12-bit resolution, V.28/V.24 compliant) for seamless PLC, DAQ, or SCADA integration
• Onboard dual-color LED status indicator providing immediate visual diagnostics for power-on, ready state, fault conditions (e.g., heater timeout, sensor saturation, communication loss)
• Compact 160 × 100 × 45 mm PCB form factor with 3 mm ID inlet port—designed for direct mounting into custom gas manifolds or modular analyzer chassis

Sample Compatibility & Compliance

The AGM module supports both single-gas and multi-gas configurations through application-specific optical filter selection and firmware mapping. It operates across a volumetric concentration range spanning from sub-ppm detection limits (<1% FS LOD) up to 100% CH₄—making it suitable for landfill biogas monitoring, HVAC CO₂ demand-controlled ventilation, industrial furnace combustion optimization, and laboratory-grade emission testing. All materials in contact with sample gas—including O-rings, housing gaskets, and internal flow channels—comply with EU RoHS Directive 2011/65/EU and are inert to common acidic, alkaline, or hydrocarbon-rich streams. While the module itself does not carry CE marking as a standalone device (intended for integration only), its design adheres to EN 61000-6-2 (immunity) and EN 61000-6-4 (emissions) for industrial environments. When embedded in final equipment, it supports compliance pathways for ATEX Zone 2 (non-incendive design), IEC 61508 SIL-2 functional safety architecture (with external watchdog supervision), and EPA Method 21–compatible leak detection workflows.

Software & Data Management

The AGM requires no host software for basic operation—calibration and alarm thresholds are adjusted manually via precision potentiometers. However, SensorsEurope provides a Windows-based Configuration Utility (free download) that enables advanced diagnostics via RS232, including real-time raw ADC values, heater duty cycle logging, internal temperature telemetry, and pressure sensor readout (when equipped). Firmware updates are delivered as signed binary packages validated via CRC-32 and SHA-256 checksums. For regulated environments, the utility supports audit-trail generation (user ID, timestamp, parameter change log) compliant with FDA 21 CFR Part 11 Annex 11 requirements when deployed on validated IT infrastructure. Data export formats include CSV and XML, compatible with LIMS platforms such as Thermo Fisher SampleManager and LabWare LIMS. No cloud connectivity or remote access capabilities are implemented—ensuring data sovereignty and eliminating attack surface for OT-critical deployments.

Applications

• Continuous emissions monitoring systems (CEMS) for municipal waste incinerators and biogas upgrading plants
• OEM integration into portable multi-gas detectors used by occupational health & safety officers (per EN 50104 and EN 45544 standards)
• Indoor air quality (IAQ) controllers in smart buildings—leveraging CO₂ feedback for dynamic ventilation rate modulation
• Automated fermentation monitoring in pharmaceutical bioreactors and food-grade anaerobic digesters
• Calibration transfer standards for field-deployable gas analyzers requiring traceable NIST-traceable zero/span verification
• Research-grade atmospheric chemistry instrumentation for eddy covariance flux towers and mobile lab vans

FAQ

Is the AGM module certified for use in hazardous areas?
No—the AGM is designed as an intrinsically safe component for integration into certified end equipment. It meets non-incendive circuit requirements per IEC 60079-11 but requires full system-level ATEX or IECEx certification by the OEM integrator.

Can the module be calibrated for gases not listed in the standard specification (e.g., SF₆ or C₂H₆)?
Yes—custom optical filter sets and calibration curves can be commissioned directly through SensorsEurope’s Application Engineering Group, subject to minimum order quantities and spectral feasibility assessment.

What is the recommended recalibration interval under continuous operation?
Per ISO 14644-3 and ASTM D6196 guidance, annual zero-and-span verification is advised; however, field validation using certified reference gases every 6 months is strongly recommended for applications requiring <±2.5% total uncertainty.

Does the module support Modbus RTU or CAN bus communication?
Not natively—only RS232 (TTL/line driver) and analog outputs are provided. Protocol translation to Modbus or CAN must be implemented externally via a gateway or microcontroller layer.

Is condensation protection included for high-humidity sampling?
The module is rated for 0–95% RH non-condensing operation. For saturated or dew-point-exceeding streams, SensorsEurope recommends upstream Nafion™ dryers or chilled-mirror conditioning—neither of which is integrated into the AGM PCB.