MQ7 (CO),MG811(CO2),MQ4(CH4),MQ135 Sensors-how to use them

giorgos · **Joined:** Fri Aug 19, 2011 8:50 am **Posts:** 9

hi guys,

I 've bougth these sensors from cooking-hacks,
Is there any tutorial how to connect them in Arduino Mega2560? Can somebody help me?
MQ7 (CO)
http://www.cooking-hacks.com/index.php/mq7-co.html
MG811 (CO2)
http://www.cooking-hacks.com/index.php/mg811-co2.html
MQ4 (CH4) - METHANE SENSOR
HTTP://WWW.COOKING-HACKS.COM/INDEX.PHP/MQ4-CH4.HTML
MQ135 - AIR QUALITY SENSOR
HTTP://WWW.COOKING-HACKS.COM/INDEX.PHP/ ... ALITY.HTML
3 x PCB Gas Sensor
http://www.cooking-hacks.com/index.php/ ... r-pcb.html

regards,
giorgos

libelium-dev · **Joined:** Mon Sep 28, 2009 11:06 am **Posts:** 2198

Hi giorgos,

We don't have tutorial for those sensors, just the data sheet that you can download.
Some indications:
- You have to power the heating resistor with 5V
- Wait for a time
- Meassure the resistor output connected with a voltage divider.

regards