Winsen MQ138 VOC Gas Sensor - SnO2 Semiconductor, 5-500 ppm Range
The Winsen MQ138 is a semiconductor VOC gas sensor module designed for detecting a range of organic vapors including toluene, acetone, and alcohol. It operates on a 5V supply and provides an analog output signal, making it compatible with microcontrollers like Arduino, ESP32, and Raspberry Pi for air quality monitoring projects.
Features
- Detects multiple VOCs: Toluene, acetone, alcohol, hydrogen, and methanol.
- Wide detection range from 5 to 500 ppm for comprehensive air quality assessment.
- SnO2 semiconductor sensing element with high sensitivity (Rs(air)/Rs(50ppm toluene) ≥ 2).
- Standard 5.0V ±0.1V heater voltage (AC or DC) with low power consumption (<900mW).
- Bakelite base with metal cap encapsulation for stable performance.
Out of stock
The Winsen MQ138 VOC gas sensor utilizes a tin dioxide (SnO2) semiconductor as its sensing material. In clean air, the conductivity of the SnO2 layer is low. When exposed to reducing gases like VOCs, the conductivity increases proportionally to the gas concentration. This change in conductivity can be converted into a corresponding output voltage signal via a simple external load resistor circuit.
The sensor requires a preheat time of over 48 hours for optimal stabilization and features a standard bakelite and metal cap construction. It is designed for operation under controlled test conditions of 20°C ±2°C and 55% ±5% relative humidity to ensure consistent sensitivity readings. Its output voltage is specified to be ≥0.5V when exposed to 50 ppm of toluene.
Additional Information
| Weight | 0.0041 kg |
|---|---|
| Dimensions | 6 × 4 × 3 cm |
