31. MQ2 Gas Sensor

31.1. Introduction

MQ2 Gas sensor is used in gas leakage detecting equipments in consumer and industry markets, this sensor is suitable for detecting LPG, i-butane, propane, methane ,alcohol, hydrogen and smoke.

microbitplanetX\./images/05031_01.png

31.2. Characteristic


  • Designed in RJ11 connections, easy to plug.

31.3. Specification


Item Parameter
SKU EF05031
Connection RJ11
Type of Connection Analog output
Working Voltage 3.3V

31.4. Outlook


microbitplanetX\./images/05031_02.png

31.5. Quick to Start


Materials Required and Diagram


  • Connect the MQ2 Gas sensor to J1 port and the OLED to the IIC port in the Nezha expansion board as the picture shows.

microbitplanetX\./images/05031_03.png

Note: A preheating for 3 minutes after powering on is required before using.

31.6. MakeCode Programming


Step 1

Click “Advanced” in the MakeCode drawer to see more choices.

../_images/05001_04.png

We need to add a package for programming, . Click “Extensions” in the bottom of the drawer and search with “PlanetX” in the dialogue box to download it.

../_images/05001_05.png

Note: If you met a tip indicating that the codebase will be deleted due to incompatibility, you may continue as the tips say or build a new project in the menu.

Step 2

Code as below:

../_images/05031_06.png

Result

  • The value detected from MQ2 Gas sensor displays on the OLED screen.

31.7. Python Programming


Step 1

Download the package and unzip it: PlanetX_MicroPython

Go to Python editor

../_images/05001_072.png

We need to add enum.py and smoke.py for programming. Click “Load/Save” and then click “Show Files (1)” to see more choices, click “Add file” to add enum.py and smoke.py from the unzipped package of PlanetX_MicroPython.

../_images/05001_081.png ../_images/05001_091.png ../_images/05031_10.png

Step 2

Reference

from microbit import *
from enum import *
from smoke import *
smoke = SMOKE(J1)
while True:
    display.scroll(smoke.get_smoke())

Result

  • The value detected from MQ2 Gas sensor displays on the micro:bit.

31.8. Relevant File


31.9. Technique File