MQ-135 (MQ-ST) Air Quality Monitoring

Name: MQ-135 (MQ-ST) Air Quality Monitoring
SKU: TS-P1430
Availability: InStock

The SnO₂ sensing layer in the MQ-135 has high resistance in clean air. When harmful gases are present, they react with oxygen ions on the sensor’s surface, reducing resistance and increasing the output voltage.

$3.95

10 in stock

This item: MQ-135 (MQ-ST) Air Quality Monitoring

10 in stock

$3.95

AM2302 DHT22 Digital Temperature Humidity Sensor

1 × AM2302 DHT22 Digital Temperature Humidity Sensor

25 in stock

$7.95

Title	Qty	Discount
Qty Discount	4 - 9	5% $3.75
Qty Discount	10 +	8% $3.63

SKU: TS-P1430

Categories:Components & Parts, Gas Sensor

Description

Additional information

Applications

Support & Utility

Q & A

The MQ-135 (MQ-ST) is a semiconductor gas sensor widely used for monitoring air quality.

It can detect a variety of harmful gases, including ammonia (NH₃), nitrogen oxides (NOₓ), alcohol, benzene, smoke, and carbon dioxide (CO₂). Its SnO₂ (tin dioxide) sensitive layer changes resistance in the presence of these gases, providing an analog output that reflects the air quality level.

Specifications:

Gas sensor – MQ-135 (MQ-ST)
High-sensitivity Gases: NH₃, NOₓ, alcohol, benzene, smoke, CO₂
Low Sensitivity:
Detection range: 10 – 1,000 ppm
Heater voltage (V<sub>H</sub>): 5V ±0.2V
Heater Resistance: 31 Ω ±3 Ω
Load Resistance: Adjustable (typically 20 kΩ)
Heater Consumption: ≤900 mW
Preheat time: 24 hours for best stability
Output type: Analog voltage (0–5V)
Dimensions: 18mm Diameter, 17mm High excluding pins, Pins – 6mm

Package Includes:

MQ-135 (MQ-ST) Air Quality Monitoring

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