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Detect Gas Changes with a Practical Air Sensor
The Gas Sensor MQ135 is a gas sensor with uart designed for air-quality projects, leak alerts, and ventilation monitoring. It is a practical fit for makers, students, and engineers who want reliable sensor data in embedded builds.
Key details include Working voltage: DC 5V; Interface: UART.
Important: Most gas and chemical sensors work best after warm-up and calibration. Readings can drift with temperature, humidity, and sensor age.
Why you’ll love it
- Power range: DC 5V
- Current draw: 150mA
- Useful spec: TTL output
- Compact size: 32mm x 22m x 27mm(HIGH 27mm)
- Easy wiring: UART
- Maker-friendly build: Easy to use in prototypes, classroom projects, and custom electronics
Compare with similar products
| Product | Sensor style | Standout |
|---|---|---|
| Gas Sensor MQ135 | gas sensor with UART | Current item |
| Gas Sensor MQ5 Analog LPG For Arduino | gas sensor with analog output | analog output, digital output |
| Gas Analog Smoke LPG CO Sensor MQ2 | gas sensor with analog and digital output | adjustable sensing range, analog output |
| Gas CO Combustible Analog Sensor MQ9 For Arduino Gravity | gas sensor with analog output | analog output, gas detection |
What you can build
This sensor is a good fit for gas leak alarms, indoor air monitors, safety demos, ventilation control, and science projects.
Starter bundles
Pair it with an Arduino-compatible board, ESP32, or Raspberry Pi, plus a breadboard or jumper wires for quick setup and testing.
Recommended add-ons
Useful add-ons include fresh-air test setup, an enclosure with vents, and a display for local readout, depending on how you plan to power, mount, and log the sensor.
Technical specifications
| Product | Gas Sensor MQ135 |
|---|---|
| Working voltage | DC 5V |
| Working Current | 150mA |
| DOUT | TTL output |
| AOUT | Analog output |
| Dimension | 32mm x 22m x 27mm(HIGH 27mm) |
| Preheat time | Over 20s |
| Interface | UART |
Wiring & usage notes
Connect power and ground, then wire TX and RX to a serial-capable controller at the correct logic level and baud rate. Most gas and chemical sensors work best after warm-up and calibration. Readings can drift with temperature, humidity, and sensor age.
What’s in the box
1 × Gas Sensor MQ135
Frequently Asked Questions
What does the Gas Sensor MQ135 measure?
It is designed to measure gas concentration changes in air.
Can I use it with Arduino, ESP32, or Raspberry Pi?
Yes. It is well suited for common maker and embedded platforms, as long as you power it at the correct voltage and match the signal level to your controller.
How do I connect this UART sensor?
This version uses UART or serial output, so you connect power plus TX and RX at the correct logic level.
Does it need calibration?
Yes. Chemical and gas sensors usually need warm-up time, calibration, and periodic checking if you want stable readings.
Is it good for prototyping?
Yes. It is a practical choice for learning, proof-of-concept builds, and small automation projects.
Manila stock. Order before 16:00 PHT, ships today via J&T or LBC. Provincial: 1–3 working days.
Schools / class POs: we accept Purchase Orders for accredited schools and universities. contact us with your PO details.
Returns: 7-day inspection window for DOA units. Email proof of issue and we ship a replacement.
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