MQ7 gas sensor calibration for PPM output

Projects General Guidance
1

Dear Sir,

I have MQ-7 Gas Sensor module for carbon monoxide(CO) Arduino Compatible. I can get the analog serial reading 0 to 1023. How can I get the gas level in PPM range ?

In the data sheet it shows a graph of Rs/Ro vs ppm. But should I want to calibrate this sensor module as it shown in data sheet ? Is this a calibrated sensor?

Please tell me how to get the gas level in ppm range and its code.

Sensor >> http://www.ebay.com/itm/140772999740?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649
Data Sheet >> http://www.elechouse.com/elechouse/images/product/MQ-x/MQ-7.pdf

I must be thankful to you if you will kindly reply this soon.

Thanks.

2

You should read the discussion from two years ago:

http://forum.arduino.cc/index.php?topic=55799.msg399839#msg399839

3

As far as I know, you need a known concentration of CO to calibrate this sensor, I also have one of those and I'm also facing the same problem.

4

@Abkad:

Do NOT post the same question in different parts of the forum

This is called cross-posting, because it makes people CROSS and wastes time.

Duplicates deleted.

5

Hi Abkad!
Did you have any lucky with this module? Im so lost with the analog output.

According to the datasheet this module detects between 10-1000ppm, so if i put the sensor inside of a upside down glass with a candle, this mean that the higher value would be match with 1000ppm? I kown that is a rough approximation, but I dont have any other idea.

Thks!!