Brief Overview of Carbon Dioxide Sensors

In today’s era of health and sustainability, carbon dioxide (CO2) concentration has become a key indicator for evaluating air quality. Excessive CO2 can not only affect human comfort but also cause dizziness, reduced concentration, and other issues. As a professional company with over 40 years of experience in gas sensing technology, Nexisense is committed to providing reliable CO2 sensor solutions. This sensor is regarded as the "breathing detector" for environmental monitoring, precisely capturing changes in ambient CO2 to help users achieve intelligent regulation. This article briefly explains its definition, working principle, core features, application scenarios, and selection recommendations, enabling readers to quickly grasp the essence of this technology and understand how to apply it in daily and professional environments to improve life and work efficiency.

Working Principle of Carbon Dioxide Sensors

Carbon dioxide sensors mainly use NDIR (Non-Dispersive Infrared) technology, a mature method based on infrared absorption spectroscopy. In short, CO2 molecules strongly absorb infrared light at a specific wavelength (about 4.26 μm). The sensor contains an infrared light source, gas chamber, and detector. When infrared light passes through the gas sample, CO2 absorbs part of the light energy, reducing the intensity reaching the detector. By comparing the change in light intensity before and after absorption, the sensor calculates CO2 concentration and outputs it in ppm (parts per million).

This principle offers advantages such as non-contact measurement, no chemical reagent consumption, and independence from oxygen concentration. Nexisense sensors optimize the optical path design to ensure stable output even in complex environments. For example, in enclosed spaces, they can accurately detect changes from 400 ppm (normal atmospheric level) to several thousand ppm, providing real-time data support.

Core Features

Nexisense CO2 sensors are known for high precision and reliability, suitable for multiple needs.

High Precision and Long Lifespan: NDIR technology is highly interference-resistant, avoiding effects from dust, water vapor, or other gases, with an accuracy of ±50 ppm. Even during long-term operation, it maintains stable performance, with a typical lifespan exceeding 10 years, outperforming low-cost alternatives and ensuring investment return.

No Oxygen Dependence: Unlike other sensor types, NDIR does not rely on oxygen, making it ideal for oxygen-deficient or enclosed environments such as basements or fermentation tanks. This expands its application range and avoids failure risks under extreme conditions.

Wide Monitoring Range: Common ranges cover 400–5000 ppm, suitable for indoor air quality monitoring; high-end models extend to 100% for industrial high-concentration needs. Nexisense product line includes TX640-J811 CO2 sensor, TX640-J812 low-power CO2 sensor, ultra-compact laser CO2 probe, TX750-J122 infrared CO2 sensor, TXZ19D infrared CO2 sensor, TX750-J161 infrared CO2 sensor, TX750-J121 infrared CO2 sensor, TX721-A1 infrared CO2 sensor, TXZ19E infrared CO2 sensor, and TX750-J193 infrared CO2 sensor. These models support various interfaces and power options for easy integration.

Additionally, low-power design allows some models to operate on batteries, enabling portable applications.

Typical Application Scenarios

The practicality of CO2 sensors spans multiple fields, helping users achieve intelligent management.

In building energy efficiency, they work with ventilation systems: when CO2 exceeds 1000 ppm, ventilation increases automatically to maintain fresh air while avoiding energy waste. In offices or malls, this demand-based control reduces energy consumption by over 15%, improving productivity.

Agriculture is another highlight. In greenhouses, CO2 is critical for photosynthesis. Sensors monitor concentrations in real-time; when below 800 ppm, CO2 fertilization is applied automatically, promoting crop growth and increasing yield by 10–30%. For example, in vegetable cultivation, this has become standard in modern agriculture.

In industrial safety, sensors monitor enclosed spaces in fermentation, brewing, or storage to prevent CO2 accumulation and suffocation risk. When linked with alarm systems, personnel can be evacuated promptly.

In environmental monitoring, portable CO2 detectors assess air quality, helping homes or schools maintain comfort. Nexisense low-power models are ideal for IoT integration, supporting remote data viewing and promoting smart city development.

Selection and Usage Recommendations

When selecting CO2 sensors, decisions should match the application scenario. For industrial needs, prioritize NDIR-based products for high precision and stability. Nexisense TX series excels in this area, supporting explosion-proof certifications for high-risk environments.

For home or commercial use with limited budgets, electrochemical options may be considered, but NDIR remains the long-term choice. Pay attention to range matching: indoor usually 400–5000 ppm, industrial higher. Install at occupant height, avoid direct sunlight or heat sources. Annual calibration maintains accuracy. Nexisense offers customization, including output signal adjustment (4–20mA or RS485) or packaging, facilitating seamless integration.

Many customers have applied these recommendations to transition from passive monitoring to active regulation, significantly improving system efficiency.

FAQ

1. What is the working principle of a CO2 sensor? NDIR-based, calculating CO2 concentration via infrared absorption without chemical reactions.

2. What is the accuracy of NDIR sensors? Typically ±50 ppm, highly interference-resistant, suitable for long-term stable monitoring.

3. Why does NDIR not require oxygen? Purely optical measurement, independent of chemical reactions, suitable for oxygen-deficient environments.

4. What is the common measurement range? 400–5000 ppm for indoor, high concentrations up to 100% for industrial applications.

5. How is it used for building energy efficiency? Linked with ventilation, automatically adjusts airflow based on CO2 levels to save energy.

6. What is its role in agriculture? Controls greenhouse CO2 fertilization, promoting growth and increasing yield.

7. What is the sensor lifespan? NDIR type typically over 10 years, low maintenance.

8. Do Nexisense products support customization? Yes, range, interface, and explosion-proof level can be adjusted.

9. How does it differ from electrochemical sensors? NDIR is more stable, oxygen-independent, though slightly higher cost.

10. Installation considerations? Avoid heat sources and vents, calibrate regularly for accuracy.

Conclusion

CO2 sensors based on NDIR technology provide high-precision, oxygen-independent monitoring, serving as vital tools for environmental management and energy optimization. From building ventilation to agriculture and industrial safety, Nexisense solutions enable precise regulation, safeguarding health and efficiency. In the carbon-neutral era, this technology is not only a monitoring device but also a facilitator of sustainable living. Proper selection and application bring significant long-term benefits, promoting greener, smarter space management.