All Products Gas Sensor

MQ-3 / The MQ-3 is a semiconductor gas sensor specifically designed for detecting alcohol (ethanol) vapor in air, widely used in breath analyzers and alcohol detection systems. It offers high sensitivity to alcohol gases while maintaining good resistance to interference from gasoline, smoke, and other vapors.<br><br>The sensor operates using a tin dioxide (SnO₂) sensing element whose conductivity increases in the presence of alcohol gas. As the gas concentration rises, the sensor’s resistance changes accordingly, allowing the output signal to be processed for accurate alcohol level detection.<br><br>With a typical detection range of approximately 25 ppm to 500 ppm for ethanol, the MQ-3 provides fast response time, stable performance, and long operational life. It operates at a standard heater voltage of 5V and requires a simple external circuit for signal conditioning.<br><br>MQ-3 modules often include both analog and digital outputs, enabling easy integration with microcontrollers such as Arduino and embedded systems. The sensor’s adjustable sensitivity and reliable performance make it suitable for portable alcohol detectors, industrial safety systems, and IoT-based monitoring applications.<br><br>Thanks to its low cost, high sensitivity, and ease of integration, the MQ-3 is one of the most commonly used alcohol gas sensors in both consumer and industrial electronics.
MQ-3

Description: The MQ-3 is a semiconductor gas sensor specifically designed for detecting alcohol (ethano ...
Package: TRAY | MOQ: 500 | MPQ: 500

4OXV / The 4OXV is a high-performance electrochemical oxygen (O₂) gas sensor from Honeywell City Technology, designed for accurate oxygen level measurement in industrial safety and environmental monitoring applications. It belongs to the CiTiceL® sensor family and is widely used in portable and fixed gas detection systems.<br><br>The sensor operates using electrochemical technology, providing a linear and stable output proportional to oxygen concentration. It offers a typical measurement range of 1–25% oxygen by volume, with overload capability up to 30% O₂, ensuring reliable operation even in varying environmental conditions.<br><br>With a fast response time of less than 15 seconds (T90) and high accuracy, the 4OXV ensures rapid detection of oxygen level changes, making it ideal for life-safety applications. It produces a typical output signal of approximately 0.10 mA in ambient air and maintains low drift over time.<br><br>The sensor is designed for durability and long-term use, offering an expected operational life of up to 24 months in air. It operates within a temperature range of -20°C to +50°C and supports a wide humidity range, ensuring stable performance in harsh environments.<br><br>Thanks to its robust design, high reliability, and immunity to false alarms, the 4OXV is widely used in applications such as personal gas detectors, industrial safety systems, medical equipment, confined space monitoring, and environmental oxygen measurement systems where accurate and dependable O₂ detection is critical.
4OXV

Description: The 4OXV is a high-performance electrochemical oxygen (O₂) gas sensor from Honeywell Cit ...
Package: TRAY | MOQ: 100 | MPQ: 100

MQ-135 / The MQ-135 is a versatile semiconductor gas sensor designed for air quality monitoring and detection of a wide range of harmful gases. It is highly sensitive to pollutants such as ammonia (NH₃), benzene, sulfide gases, smoke, and other volatile organic compounds (VOCs), making it ideal for environmental monitoring applications.<br><br>The sensor operates using a tin dioxide (SnO₂) sensing material whose conductivity increases as the concentration of target gases rises. This change in resistance is converted into an analog signal that can be processed by microcontrollers for air quality analysis.<br><br>With a typical detection range of approximately 10 ppm to 1000 ppm (and up to 10,000 ppm depending on gas type), the MQ-135 offers wide detection capability, fast response, and long operational life. It requires a 5V supply for both heater and sensing operation and consumes less than 950 mW of power.<br><br>MQ-135 modules usually provide both analog and digital outputs, enabling easy integration with platforms such as Arduino, ESP32, and other embedded systems. Adjustable sensitivity allows calibration for specific gases or environmental conditions.<br><br>The MQ-135 is widely used in applications such as indoor air quality monitoring systems, smart home devices, industrial safety equipment, pollution detection, and IoT-based environmental sensing solutions where multi-gas detection and low-cost implementation are essential.
MQ-135

Description: The MQ-135 is a versatile semiconductor gas sensor designed for air quality monitoring and ...
Package: TRAY | MOQ: 500 | MPQ: 500

MQ-4 / The MQ-4 is a semiconductor gas sensor specifically designed for detecting methane (CH₄) and natural gas concentrations in air. It is widely used in gas leakage detection systems due to its high sensitivity to methane and low sensitivity to alcohol and other interfering gases.<br><br>The sensor utilizes a tin dioxide (SnO₂) sensing material whose conductivity increases in the presence of methane gas. This change in resistance is converted into an electrical signal that can be measured via analog output, enabling accurate monitoring of gas concentration levels.<br><br>With a typical detection range of approximately 300 ppm to 10,000 ppm, the MQ-4 offers fast response time, stable performance, and long operational life. It operates at 5V and includes an internal heating element required to maintain optimal sensing conditions.<br><br>MQ-4 modules often provide both analog and digital outputs, allowing easy interfacing with microcontrollers such as Arduino and embedded systems. Adjustable sensitivity via onboard potentiometer enables customization for different detection thresholds.<br><br>The MQ-4 is commonly used in applications such as natural gas leakage detection, industrial safety systems, residential gas alarms, environmental monitoring, and IoT-based smart safety solutions where reliable methane detection is essential.
MQ-4

Description: The MQ-4 is a semiconductor gas sensor specifically designed for detecting methane (CH₄) ...
Package: TRAY | MOQ: 500 | MPQ: 500

MQ-2 / The MQ-2 is a widely used semiconductor gas sensor designed for detecting combustible gases and smoke in air. It is highly sensitive to gases such as LPG, propane, methane, hydrogen, and alcohol, making it suitable for safety and monitoring applications.<br><br>The sensor operates based on a metal oxide (SnO₂) sensing element whose resistance changes in the presence of target gases. As gas concentration increases, the conductivity of the sensor rises, producing a measurable analog output signal.<br><br>With a typical detection range of approximately 300 ppm to 10,000 ppm for flammable gases, the MQ-2 offers fast response time, high sensitivity, and long operational life. It operates at 5V and includes a built-in heating element required for accurate sensing.<br><br>The module version of the MQ-2 provides both analog and digital outputs, allowing easy integration with microcontrollers such as Arduino and other embedded platforms. Adjustable sensitivity via onboard potentiometer enables flexible threshold configuration for different applications.<br><br>The MQ-2 is commonly used in applications such as gas leakage detection systems, smoke alarms, industrial safety equipment, air quality monitoring, and IoT-based environmental sensing solutions where reliable detection of combustible gases is required.
MQ-2

Description: The MQ-2 is a widely used semiconductor gas sensor designed for detecting combustible gase ...
Package: TRAY | MOQ: 500 | MPQ: 500













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