Air Quality Sensor
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@jumping you will need to scale down the script obviously, in term of power it will be too short to have more than one.
@epierre said:
@jumping you will need to scale down the script obviously, in term of power it will be too short to have more than one.
thanks for your answer! please, can you explain how the following code in your sketch is related to datasheet?
- float CO_secCurve[2] = {726.7809737, -4.040111669}; //MQ135
I understand the sketch in the "Gas Detection - Example", but not the previous.
sorry for my poor english :-) -
Air Quality Index is a combination of several sensors values:
- sulfur dioxide (SO2) MQ136 / (avoid:2SH12 no datasheet)
- nitrogen dioxide (NO2) MiCS-2710 MiCS-2714 MICS-6814
- carbon monoxide (CO) MQ-7 MiCS-5525 TGS2442 MICS-6814
- ozone (O3) MQ131 MICS-2610 MICS-2614
- Particles concentration: PM2.5 and PM10 (SamYoung DSM501, Shinyei_PPD42NS, avoid: Sharp_GP2Y1010AU)
Additional gases can be interesting to track:
Current work being done:
- manage default Ro once
- take into account humidity
- manage to get proper values from TGS2600
- possibility to have a push if a value goes up too quick (for deadly gases even without calibration)
What is done:
- remove powerdown to keep heaters on
- add a five minute pre-heat on each startup
- removed the powerdown
- 2SH12 datasheet doesn't exist
WARNING: all sensors differs even within the same reference, a calibration has to be done each time. Do not rely upon a sketch result with deadly gases.
Working sketch in 1.4/1.5:
- https://github.com/empierre/arduino/blob/master/MQv01dgi_1_4.ino (for a Mega, MQ2, MQ6, MQ131, MQ136, MQ138, TGS2600, TGS2602, HCHO, Barometer BMP085, DHT11)
- https://github.com/empierre/arduino/blob/master/AirQuality-CO-NO2-NH3.ino for MICS-6814
- https://github.com/empierre/arduino/blob/master/CO2-MH-Z14.ino
- https://github.com/empierre/arduino/blob/master/DustSensor_SamYoung_DSM501.ino
- https://github.com/empierre/arduino/blob/master/DustSensor_Shinyei_PPD42NS.ino
@epierre Hi I am working on the MQ2 sensor, I want to know CO level. Did you do it before with this sensor?
I am using this module and just start work with this sensor.
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@epierre Hi I am working on the MQ2 sensor, I want to know CO level. Did you do it before with this sensor?
I am using this module and just start work with this sensor.
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@epierre is it possible that the lastest github for Samyoung 501a is not correct? Flashed it and the results are way too high (157000 mg/m3)?
@lukács-attila check wiring first, seems there are several sub version around thay may need other values from datasheet
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Ppm percentage calculations in the code seems wrong. Instead of providing rs/ro ratio to the function is transfered rs value not the ratio.
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@epierre I wonder if you looked at this sensor Figaro TGS8100:
http://www.figarosensor.com/products/entry/tgs8100.html
Looks like it is perfect for a low-powered platform.
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@rosmel said in Air Quality Sensor:
tgs8100
That's also quite a non-precise sensor if I understand correctly. Useful for general 'how's the air', but because it will respond to so many different 'polutants' you never know which of those polutant is the culprit.
You will find code in the forum for good CO, CO2 and fine dust sensors.
