Could please anyone advise for the MQ 136 sensor calibration.
I got the resistance analogue value of the sensor from that how to get the exact PPM value.
The datasheet will normally give strong clues
How is this "installation and troubleshooting"?
The MQ 136 sensor has 4 pins. I was installed sensors as follows
VCC - 5V,
Aout- pin Analog A0,
Dout- not used.
Gnd- Gnd.
Examples,
I have received the analog value as 602, 604 and I was used to do the algorithms which calculate the PPM value as 4.5 PPM but unfortunately the PPM value is not reliable and I was checked with the gas detector which gives 5.5 PPM and even when sensor was disconnected the value remains 4 PPM.
@mdimran-01, welcome.
Your topic has been moved to a more suitable location on the forum. Installation and Troubleshooting is not for problems with (nor for advice on) your project 
See About the IDE 1.x category.
Disconnected inputs float and pick up noice from the environment.
Calibrate the device using one or more known gas concentrations, following the general instructions in this tutorial.
Thanks for the information.
Is it possible to share whether any specific algorithms to calculate the H2S in PPM for the MQ 136 sensor.
The MQ sensors respond to many different gases, and can be used to estimate the concentration of any one gas, in isolation.
The sensor needs to be individually calibrated for each specific gas. And, of course, you need some means of knowing which particular gas is present.
Yes the MQ136 used to monitor the NH3, H2S, Propane etc. But the particular gas concentration of MQ136 which I used to monitor was H2S.
This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.