Why NDIR Is a Superior Solution for Methane Detection — In-Depth Analysis of TX711-A70's Core Technology

Methane is one of the most critical and challenging target gases in combustible gas detection. Colorless, odorless, and highly diffusive, methane leaks can easily lead to safety incidents. As application scenarios extend from industrial sites to urban gas networks, inspection routines, distributed IoT systems, and battery-powered devices, traditional detection solutions show limitations in reliability, lifespan, and power consumption.

In this context, NDIR (Non-Dispersive Infrared) technology has emerged as the industry-recognized evolution path for methane sensors. The TX711-A70 battery-powered low-power infrared methane sensor from Nexisense exemplifies this trend.

From "Can It Detect?" to "Is It Reliable?": The Evolution Logic of Methane Detection Technology

Early methane detection focused on whether gas was present. Catalytic combustion and electrochemical technologies offered cost and maturity advantages at the time. However, as environments became more complex, these methods revealed limitations:

• Susceptible to oxygen concentration variations

• Respond to multiple combustible gases, increasing false alarm risk

• Sensor elements consume over time, limiting lifespan

• Unsuitable for long-term battery-powered applications

When detection needs shift from "functional" to "stable and reliable over time," selecting the right technology becomes crucial.

NDIR Principle: Methane Detection Based on Physical Properties

Unlike chemical-reaction-based solutions, NDIR fundamentally measures gas via molecular spectral absorption characteristics.

Methane Infrared Absorption Characteristics

Methane molecules have a significant and stable absorption peak around 3.3 μm in the mid-infrared. NDIR sensors:

• Emit infrared light at a specific wavelength

• Pass the beam through the target gas

• Measure light intensity attenuation

• Calculate methane volume fraction or concentration using the Beer–Lambert law

The core advantage: the measurement relies on the gas's "fingerprint" rather than a reaction result.

Technical Advantages of TX711-A70 Derived from NDIR Principles

High Selectivity: Reduce False Alarms at the Source

The TX711-A70 uses a narrow-band optical filter to respond only to methane's characteristic absorption wavelengths. Common interfering gases such as alcohol, hydrogen, carbon monoxide, and hydrogen sulfide have minimal impact on detection results even at higher concentrations. This "look only at the target wavelength" design maintains stable readings in complex gas environments, ideal for urban gas and public safety scenarios.

Oxygen-Independent: Adapt to Complex Environments

NDIR does not involve combustion or electrochemical reactions, so:

• No oxygen is required

• Performance is unaffected by oxygen fluctuations

Whether in high-altitude regions, underground tunnels, or enclosed/inert gas environments, the TX711-A70 maintains consistent detection performance—something catalytic combustion sensors cannot achieve.

Long Lifespan Design: Suitable for Long-Term, Maintenance-Free Applications

The core components of TX711-A70 are the infrared light source and detector, which are non-consumable. Under normal operating conditions, the expected lifespan is 5–10 years. Compared with catalytic elements that usually require replacement every 1–3 years, this design reduces maintenance costs and significantly improves overall system reliability, especially for large-scale deployments.

Built-In Temperature Compensation: Address Real-World Variability

Environmental temperature affects:

• Gas density

• Infrared light source intensity

• Detector response characteristics

The TX711-A70 integrates a high-precision temperature sensor and compensation algorithm to correct system errors in real time, ensuring reliable and comparable measurements under extreme temperatures.

Engineering Value: Low Power and Miniaturization Are Not Automatic

Precision Optical Design

Within limited packaging space, multiple reflections and optimized light path length increase effective absorption path, improving signal-to-noise ratio and reducing reliance on light source power.

Pulsed Power and Intelligent Signal Processing

The TX711-A70 employs pulsed infrared source driving, active only during sampling windows, combined with algorithmic filtering and processing. This greatly reduces average power consumption, enabling long-term battery operation. Such design reflects integrated optical, electrical, and algorithmic engineering rather than isolated optimization.

Why TX711-A70 Is a "Universal" Methane Detection Solution

TX711-A70 is a highly versatile platform suitable for:

• Urban gas leak monitoring

• Portable inspection devices

• IoT endpoints

• Distributed safety monitoring nodes

Its technical characteristics naturally align with industry demand for "low power + high reliability + minimal maintenance."

FAQ

• Is NDIR suitable for long-term outdoor use? Yes. NDIR adapts well to environmental variations, and with proper protection, can be used in various outdoor scenarios.

• Does battery power affect response speed? No. Pulsed operation balances power consumption and response speed at an engineering level.

• Is NDIR only suitable for methane? The principle can be extended, but TX711-A70's optical system is optimized for methane, providing higher specificity.

  
  

Conclusion: A More Robust Methane Detection Technology Path

The TX711-A70 not only introduces a new sensor model but clearly demonstrates an NDIR-based, engineering-supported methane detection technology path. For applications seeking long-term reliability, low maintenance, and high data confidence, this physical-property-based approach is becoming the industry consensus. Nexisense provides a mature and practical solution with TX711-A70 in this direction.