I would like to make a CO2 sensor to go into the back of a truck carrying chickens.

I would like to know if the CO2 level is rising and I would also like to know before it gets dangerously high.

I can buy locally the MQ-135 GAS SENSOR and want to know if this is suitable and if I would have to add any other circuit.

The supply voltage would be 12 Volts. From a 7Ah Sealed Lead Acid battery

 

That sensor is not designed specifically to measure CO2. In the case of livestock, it will be severely overwhelmed with NH3. The CO2 concentration in air is about 0.04% or 400ppm.

The other consideration with gas sensors and detection instruments is you have to calibrate them. This requires applying a gas sample of known concentration in the range of your interest.

 

What is considered the safe level for chickens? Is there also a limit on ammonia?

If there is not a specific detector, a little pre-chemistry or selective adsorption/entrainment can distinguish between CO2 and NH3.

John

 

The MG811 sensor appears to be a better choice for CO2.

http://www.futurlec.com/Gas_Sensors.shtml

For more accurate measurements, you need to use instruments based on IR absorption spectrum. Check out the MH-Z14 CO2 Module:

http://www.futurlec.com/CO2_MODULE.shtml

 

Thank you for all the advice and Help. After reading everything here I believe its probably best that I buy a unit that is already made and can be used in my application. Now to find the unit.

 

https://www.lumasenseinc.com/EN/products/gas-sensing/andros-oem-gas-modules/andros-6511.html

Have a look at these IR absorption units.