MQ-135 Gas Detector quick start

[@noelaquilizan7881]

Hi, im trying to know what is the right value of ppm while detecting the ammonia? do you have any idea?

[@Cosmos-2022]

facebook.com/groups/916444195036070/

[@MiG-25IsGOAT]

there is no "right value", it depens on the intensity, the more the ammonia the greater the value

[@doubrajonathan7148]

Please I need help with the physical connections of the MQ 135 with a raspberry pi through a breadboard, including the MCP3008-I/P 10-Bit ADC. Please it's urgent for a school project

[@dewipuspita5917]

Its in github raspberry pi tutorial gas sensor mq

[@yashkhavnekar6330]

I'm just getting the value 1023 constantly there's no change whichever gas I try detecting from the sensor!!!

[@garimabhardwaj6607]

Sir, could you please provide the code being used. Waiting in anticipation.

[@gabrielmeister3639]

legends say he's still waiting

[@wotorufaeserifa7589]

Hello, can the sensor be set to detect only a specific gas, maybe alcohol, using the Potentiometer or a load resistor?

[@raulacevedo8336]

The sensor can not differentiate between chemical species, it detects a concentration and sends a voltage accordingly.

[@sagargodase5182]

Can you provide simple step with detail about analogRead to PPM conversation..?? Hoping for positive response... :-)

[@firdauszainuddin9814]

sir, its been 1 year. i have the same question too . help me pls

[@Cosmos-2022]

@@firdauszainuddin9814 facebook.com/groups/916444195036070/

[@Rishabh-coder-pub]

hello sir , in place of 1024 ,it should be 1023. because converting through 10 bit ADC converter , analog value ranges from 0-1023.

[@rishabhjain2559]

What did you meant by scaling value. could not understand why you divided sensor value by 1024 and multiplied it by 5 . please help me in clearing this doubt

[@huzniey]

hello. have you found this answer?

[@rishabhjain2559]

5 is the voltage supplied to the sensor .1024 is due to the address bus of arduino(2^10).I used esp32 which has address bus of 14 bits so scaled it by 4096(2^14)

[@MatthewHartsuch]

this is good, I have 9 different gas sensors tho that I havent had a chance to use, I wonder if they all work this way

[@raulacevedo8336]

If they have pins for ground, Vcc and analog out then yes.

[@Maxmudjon]

where scetch ?

[@jackz8480]

How do I make an app to communicate with it?

[@satyanarayanareddykondared1227]

Hi, I'm working with MQ135 sensor to get Gas concetration on my Raspberry Pi 3B+. We are using MCP3008 to connect MQ135 gas sensor to Pi. Please help me out in connection and python code. Thanks in advance.

[@yusufabubakar9862]

Any luck on it

[@Rishabh-coder-pub]

can you please provide the code

[@salvatore9653]

You cannot directly scale it like this since the calibration curve of MQ135 is linear in the log log scale... the way you calculate PPM is misleading.

[@huzniey]

Hi. Can I know the correct way to calculate PPM. Hoping for positive reply. Thank you sir.

[@salvatore9653]

@@huzniey CHeck the datasheet of the sensor and do a curve fit. Your calculation has to be related to the calibration curve provided by the manufactures.