CUBIC INSTRUMENTS Gasboard-3000UV UV Differential Optical Absorption Spectroscopy (DOAS) Nitrogen Oxides Analyzer

Overview

The CUBIC INSTRUMENTS Gasboard-3000UV is an online, single-channel nitrogen oxides (NO_x) analyzer engineered for continuous, high-stability measurement of nitric oxide (NO) and nitrogen dioxide (NO₂) in ambient air and exhaust gas streams. It employs ultraviolet differential optical absorption spectroscopy (UV-DOAS), a well-established, non-dispersive optical technique that leverages the unique absorption fingerprints of NO and NO₂ in the 190–230 nm spectral region. Unlike chemiluminescence or electrochemical methods, UV-DOAS enables simultaneous, interference-resistant quantification without consumables or catalytic converters—eliminating cross-sensitivity to SO₂, CO, hydrocarbons, and water vapor under typical operating conditions. The instrument features a compact, temperature-stabilized optical cell with direct-path geometry, optimized for minimal light path attenuation and high signal-to-noise ratio. Its design conforms to the photometric and metrological requirements specified in Chinese national standards GB 3847–2018 (for diesel vehicle emissions) and GB 18285–2018 (for gasoline vehicle emissions), achieving Class 00 accuracy per regulatory verification protocols.

Key Features

• UV-DOAS core technology ensures real-time, simultaneous dual-species detection (NO and NO₂) with inherent immunity to common combustion gas interferences
• Short-path, high-transmission optical cell minimizes particulate deposition effects and eliminates need for frequent optical cleaning cycles
• Zero-air pump integrated into the chassis enables fully automated, periodic air-based zero calibration—no external gas cylinders required
• Flow-insensitive measurement architecture: sample flow rate variations between 0.5–2.0 L/min exert negligible impact on concentration output stability
• Onboard self-diagnostic system continuously monitors lamp intensity, detector response, optical alignment, and signal baseline drift—logging fault codes for predictive maintenance
• Rugged industrial enclosure rated IP54 for deployment in vehicle inspection bays, stack monitoring stations, and mobile emission testing platforms

Sample Compatibility & Compliance

The Gasboard-3000UV is validated for use with dry or humidified gas samples containing particulate concentrations ≤10 mg/m³ (as measured by gravimetric filter analysis). It supports inlet temperatures up to 60 °C when equipped with optional heated sampling line (not included). The analyzer meets electromagnetic compatibility (EMC) requirements per GB/T 18268.1–2010 and environmental stress testing per GB/T 2423 series. While not certified to ISO/IEC 17025 for accredited testing, its measurement traceability aligns with NIST-traceable UV radiometric standards via factory calibration using certified reference gases (CRM NO and NO₂ mixtures). Data integrity complies with GLP-aligned audit trail practices through timestamped calibration logs and configuration change records stored in non-volatile memory.

Software & Data Management

The device operates firmware v3.2+ supporting Modbus RTU over RS-485 and ASCII protocol over RS-232, enabling seamless integration into SCADA, CMS, or OEM test bench control systems. All communication frames include CRC-16 error checking. The embedded data logger stores 30 days of 1-second resolution concentration readings (NO, NO₂, internal temperature, zero status) with cyclic overwrite. Optional PC utility software provides remote firmware updates, spectral view diagnostics, and export to CSV/Excel formats. No cloud connectivity or proprietary cloud platform is implemented—data remains fully under user control per GDPR and local data sovereignty regulations.

Applications

• Regulatory compliance testing at motor vehicle inspection & maintenance (I/M) stations per GB 18285 and GB 3847
• Continuous emissions monitoring (CEMS) for small-scale industrial boilers and stationary combustion sources
• Engine development laboratories requiring fast-response NO_x feedback during transient dynamometer cycles
• Mobile source emission research, including PEMS (Portable Emissions Measurement Systems) integration
• Third-party environmental testing laboratories performing method validation against reference analyzers
• Academic and governmental air quality research programs focused on urban NO₂ mapping and traffic-related pollution profiling

FAQ

Does the Gasboard-3000UV require calibration gas cylinders for routine operation?

No—automatic zero calibration uses ambient air drawn by the internal pump. Span calibration requires certified NO and NO₂ standard gases at user-defined intervals (typically every 3–6 months depending on usage severity).
Can the analyzer operate unattended for extended periods?

Yes—it supports continuous 24/7 operation with built-in thermal management and watchdog timer circuitry. Internal logging and diagnostic alerts reduce manual intervention frequency.
Is the instrument compatible with existing exhaust gas analyzers from other manufacturers?

Yes—standard RS-232/RS-485 and 4–20 mA outputs allow interoperability with most OEM engine test stands, chassis dynos, and multi-gas CEMS controllers.
What maintenance is required beyond zero/span calibration?

Annual inspection of optical window cleanliness and replacement of particulate filter (if installed upstream); no lamp or detector replacement is anticipated within first 5 years of normal operation.
Does the analyzer support dual-range or auto-ranging functionality?

No—it operates in fixed full-scale ranges: 0–4000 ppm for NO and 0–400 ppm for NO₂. Range switching is not supported; users must select appropriate model variant during procurement if alternate ranges are needed.