Wireless Combustible Gas Sensor

The combustible gas sensor is based on the MQ-2 Gas sensor and responds to various combustible gases found around the home like gasoline, butane, methane, alcohol, natural gas, propane, smoke etc. This module is not calibrated but is intended to provide a convenient way to experiment with this sensor. I use it to keep an eye on the lawnmower shed where I keep gasoline, oil, paint and various other flammable liquids.

The Gas Sensor is also available with an internal temperature sensor or Temperature and Humidity sensor.

Since the MQ-2 sensor contains a heating element this requires more power than can reasonably be supplied by a battery and so is powered by a five volt wall wart. To extend the life of the MQ-2 sensor it is powered up for three minutes (three minute warm-up required for the sensor element) once an hour to take a reading.

Operation:

On power up the Wireless Sensor module applies power to the sensor, waits three minutes for the sensor to stabilize, takes the reading, checks the value against the Alarm Threshold, sets the Alarm bits accordingly and then powers the sensor off again.  It then transmits the reading and alarm status to the Sensible Living receiver.   If the reading is less than or equal to threshold the module goes to sleep for “Interval” minutes minus three (default Interval is set to sixty (60) minutes) if the reading exceeds the threshold then the on-board buzzer will sound, and immediately starts another three minute reading.  When the gas concentration drops below threshold the buzzer will stop and the new sensor reading will be transmitted to the receiver.

Like the rest of the Sensible Living sensors, the Combustible Gas sensor requires the Desktop Application and Receiver (sold separately) to let you know when there is a problem. The Desktop App can then be configured to send you a message if the sensor ever detects a combustible gas level above threshold.

Also available on this site:

• Receiver
• Mini-Plant Sensor
• Mini-Temperature Monitor
• Mini-Water leak detector
• Mini-Tilt Sensor
• Mini-Light Sensor
• Mini-General Purpose Sensor
• Temperature and Humidity Monitor
• Refrigerator/freezer temperature monitor
• Quad AC Current monitor (monitors up to four circuits simultaneously)
• Wireless MQ2 Combustible Gas sensor
• General Purpose Sensor board
• Motion Sensor
• Range Extender
• USB to Serial Adapter

Why did you make it?

I had a gas can tip over in the lawnmower shed filling the room with gas fumes. It could easily have been a disaster but fortunately I discovered it in time. I then immediately began to design this sensor. All of my sensors were built to address specific needs around my home and for my family.