Advantage of this sensor is fast and easy installing by the non qualified personal. The sensor is designed for large agriculture facility with many greenhouses where is needed to be controlled temperature and humidity, the atmospheric pressure is for control the motor of air inlet and outlet. With help of the sensor installed outside the greenhouse provide information about positive/negative pressure inside the greenhouse.
Finlay the software read accurate temp/humid value of the Si7021, and only atmospheric pressure of BMP180, the temperature sensor inside the BMP180 is used only by the sensor itself to provide accurate atmospheric pressure measurements.
The sensor can be used also for home automation, and drone applications where is needed correction of the UAV barometric sensor compared to the ground barometric sensor, also humidity measurement can help the pilot to calculate more accurate flying time.
Thanks again, learned a lot... I decide to give a try there, I also had a look on some components' datasheet and seems to be what I need... Let's see, if end up getting the boards I'll publish a review here later.
Sorry, 1 more question. At what timeframe do you expect diy packages to be for sale? I have checked with steel manufactures before for other projects, but having a small batch of steel tubes means that they will be enormously expensive and the same goes for the PCB's. The milling I can do easily at a maker space (fablab013). I am planning on a rather long, 1 storey hive, so I plan to cut the metal tubes in half and mount an extension in between.
Hi @Siddharth-Velappan
The warmup time of the MH Z19b is 3 minutes. So 2 is probably fine, but you could probably do 3 just in case. Although 2 would save your more battery time.
Do you mind explaining your setup a bit more? I would love to do something similar but I do not know where to get started with the PIC microcontroller!
@mjdula
The 85 reading is actually an error message used by the ds18b20 to indicate it has not had time to complete the processing of the reading. Most commonly this is only seen when the node first boots up and can be ignored or fixed by adding a small delay. You will find a lot of information on this if you do a google search. I have never experienced it myself but from other posts on the net it seems power supply problems and long cable runs to the sensor can also cause the error. Some have also had success by using a different resistor value. Note you only need one resistor fitted near your nodemcu not a resistor at each ds18b20.
If the 85 reading is well outside your expected reading you could just filter out any readings over 84 as well.