The MQ-2 smoke sensor is sensitive to smoke and to the following flammable gases:
The resistance of the sensor is different depending on the type of the gas.
The smoke sensor has a built-in potentiometer that allows you to adjust the sensor digital output (D0) threshold. This threshold sets the value above which the digital pin will output a HIGH signal
From my previous tutorial I made Arduino based Smoke detection system. Here, I have made IOT based Smoke detection notification system through your smart phone using Node Mcu and Blynk app
Thanks UTSOURCE.net to offer electronic components for my projectsConnections:
- VCC pin of MQ-2 is connected to 3V pin of NodeMCU.
- GND pin of MQ-2 is connected to GND pin of NodeMCU.
- A0 pin of MQ-2 is connected to A0 pin of NodeMCU.
- Positive (+) pin of Buzzer is connected to D2 pin of NodeMCU.
- GND (-) pin of Buzzer is connected to GND pin of NodeMCU.
watch the video for how to setup the blynk app it will show you step by step
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