how wide is the measuring area (meter square) [m²] of a dht22 sensor?
The sensor can only measure the temperature of the air that is touching it so only a few square millimeters and certainly not metres
What application are you thinking of using the sensor for ?
For a room, a cultivation room (Green house)
So , how much sensors needed for that application
How big is the greenhouse ?
Are you aiming to control the temperature of the greenhouse or just measure it ?
If you circulate the air in the room and can control the temperature by means of heating, cooling and ventilation then you only need one sensor
How much control over the environment do you have ?
The area is 35m² and 2 meter high
Yes i want to control the humidity an temperature
Only one mcu in the environtment
Do you have referrences about? Article or something?
Hi,
This may help;
https://www.dpi.nsw.gov.au/agriculture/horticulture/greenhouse/structures-and-technology/ventilation
Google;
greenhouse air circulation
Tom... 
No, just my common sense
Where are you stuck at the moment ? Can you read the temperature and humidity from the sensor and display them on the Serial monitor ?
How are you doing to alter the environment ?
Heating ?
Cooling ?
Ventilation ?
Suppose the temperature is outside the target range then what are you going to change to bring it back into range ? Same question for humidity
I expect that there will be a interaction between the temperature and humidity, ie change one and the other one changes too. How are you going to deal with that ?
I just want to make sure that the sensor reading is represented condition of humidity and temperature in all area of green house. Cause i only used one sensor for a room.
I doing ventilation with fan and cooling with water mist pump
in this project focuses on controlling humidity than the impact of the process on changes in temperature values will be tolerated
Hi,
Well keep the sensor away from any direct flow from the water mist, as this will degrade the sensor very quickly.
If you have ventilation, also make sure you have circulation of air around the greenhouse when the ventilation is off.
With good circulation you will only need one sensor to measure humidity and air temperature.
Can you post a plan of your greenhouse, showing where your ventilation and water mist is located and size of the building?
Tom...
For that condition mcu will activate a mist pump to bring the condition on range
The greenhouse size is 5 meter x 7 meter and 2 meter high. Fan will be install on two side of green house and nozzle will be install a long as greenhouse with ten points of mist nozzle
Thanks for your insight
This topic was automatically closed 120 days after the last reply. New replies are no longer allowed.