Gasboard-7500H Ultrasonic Oxygen Sensor by Cubic

Overview

The Gasboard-7500H is an ultrasonic oxygen sensor engineered by Cubic for simultaneous, real-time measurement of oxygen concentration and volumetric flow rate in binary gas mixtures. Unlike electrochemical or paramagnetic sensors, the Gasboard-7500H employs time-of-flight (TOF) ultrasonic transit-time differential measurement — a non-invasive, drift-free physical principle that eliminates consumables, catalytic degradation, and oxygen depletion effects. This architecture ensures stable performance across extended operational lifetimes without recalibration. Designed specifically for integration into medical and industrial oxygen generation systems — including pressure swing adsorption (PSA) units, portable concentrators, and cleanroom gas distribution panels — the sensor delivers high repeatability under variable thermal and humidity conditions. Its compact form factor and wide input voltage range (4.75–12.6 V_DC) enable seamless adoption into space-constrained embedded platforms with diverse power architectures.

Key Features

• Simultaneous dual-parameter output: oxygen concentration (0–100% vol) and volumetric flow (0–10 L/min) via single-sensor interrogation
• Full-temperature compensation across −5°C to +50°C ambient, ensuring consistent accuracy without external thermal correction algorithms
• Factory-trimmed calibration with no field recalibration required — compliant with long-term stability requirements per ISO 13485 and IEC 60601-1 for medical device integration
• Low-power operation (<35 mA avg.) and TTL-level UART digital interface simplify microcontroller interfacing and reduce system-level BOM cost
• RoHS-compliant construction and CE/EMC/CMC certifications support global deployment in regulated environments, including Class II medical equipment and industrial safety systems
• Robust mechanical design (IP20-rated enclosure) optimized for continuous operation in non-condensing environments up to 95% RH

Sample Compatibility & Compliance

The Gasboard-7500H is validated for use in binary gas matrices where oxygen is one component and the second constituent exhibits significantly different acoustic impedance — most commonly N₂ or Ar. It is not intended for multi-component or reactive gas streams (e.g., CO₂-rich or humidified CO mixtures), nor for trace O₂ detection below 0.1% vol. The sensor meets metrological requirements under China’s Measurement Law (CMC certification), conforms to EU Electromagnetic Compatibility Directive 2014/30/EU (CE marking), and satisfies RoHS 2011/65/EU restrictions on hazardous substances. While not intrinsically safe, its low-voltage operation and absence of ignition sources make it suitable for Zone 2 classified areas when integrated within certified system-level enclosures per ATEX/IECEx guidelines.

Software & Data Management

Data output is delivered via asynchronous UART (TTL 3.3 V logic) at configurable baud rates (default: 9600 bps), supporting ASCII-based command-response protocols for configuration and real-time streaming. Cubic provides open communication protocol documentation and reference firmware libraries (C/C++ and Python) for rapid integration into host controllers. All measurements include embedded timestamping and checksum validation to ensure data integrity. While the sensor itself does not store historical data or support network protocols (e.g., Modbus TCP, MQTT), its deterministic latency (<1.5 s for concentration, <0.3 s for flow) enables synchronization with external DAQ systems compliant with FDA 21 CFR Part 11 audit trail requirements when deployed in GMP-regulated manufacturing or clinical oxygen delivery infrastructure.

Applications

• Medical-grade PSA oxygen generators — real-time monitoring of product gas purity and output flow for alarm triggering and process feedback control
• Home-use oxygen concentrators — enabling closed-loop flow regulation and user-facing O₂ concentration display with minimal power overhead
• Industrial inert gas blanketing systems — verification of O₂ residual levels in N₂-purged vessels prior to welding or packaging
• Cleanroom environmental monitoring — continuous verification of nitrogen or argon supply lines for pharmaceutical and semiconductor fabrication facilities
• Research-grade gas blending stations — precise stoichiometric verification in binary gas calibration standards and analytical instrument carrier gas lines

FAQ

Does the Gasboard-7500H require periodic recalibration?
No. It is factory-calibrated for lifetime operation under specified environmental conditions. No user-accessible recalibration procedure exists, and performance remains within ±1.5% FS over its rated temperature range without intervention.
Can this sensor measure oxygen in humidified or CO₂-containing gas streams?
It is validated only for dry or moderately humid (≤95% RH, non-condensing) binary mixtures such as O₂/N₂ or O₂/Ar. High CO₂ content alters sound velocity nonlinearly and invalidates the TOF model; humidified CO or H₂ streams are outside its design envelope.
Is analog output available?
No. The Gasboard-7500H provides digital UART output only. Analog conversion must be implemented externally using a compatible microcontroller or signal conditioning module.
What is the minimum detectable flow rate?
The sensor maintains specified accuracy down to 0.1 L/min, with resolution of 0.1 L/min and response time ≤0.3 s — suitable for low-flow applications such as nasal cannula monitoring and small-bore tubing verification.
How does ultrasonic TOF measurement compare to zirconia or paramagnetic O₂ sensing?
Unlike zirconia cells (which consume O₂ and degrade at high temperatures) or paramagnetic analyzers (bulky, sensitive to vibration and magnetic fields), ultrasonic TOF offers zero consumables, immunity to poisoning, and inherently linear response across full scale — ideal for embedded, maintenance-free installations.