I want to built a capacitive rain sensor for Arduino which can tell me when it rains and how much about (drizzle, normal, heavy rain), maybe 4-5 possible states, depending on the heaviness of the rain.
I currently using a normal eBay rain sensor from China, which is based on resistance but its not very "precise" and does not work with drizzle and oxidizes after one week.
I have found the Arduino "CapacitiveSensor" library and tried to used the shield from the actual rain sensor with a plastic tape on it. I basically works, but the values fluctuate heavily. I used a 1M, 2M and 4.7M resistor between the two pins and a 100pF, 1000pF and 100nF capacitance to Ground.
Maybe you have a better idea to solve this problem, with other components or values or also a complete new circuit.
Before attempting to design and build a capacitive rain sensor, I suggest to investigate how commercial capacitive rain sensors work and how many categories of precipitation are reported.
I have already seen this document and I know how this sensor works. I don't want such a complex sensor with heater and temperature sensor. I need support with designing or creating a simple sensor.
I need support with designing or creating a simple sensor.
What reason do you have to believe that a "simple" sensor can be made to do what you want? The lack of such commercial options suggests that this is not an easy task.
I take a reading every 5 mins and save it to a flat file
Thank you! I thought that you have used the analog value to calculate the "heaviness" of the rain. Maybe I will try to interpret the analog value to get a more descriptive result!
if you look at the plots - it looks like harder rains give lower values - if you experiment with the resistor value you likely can get more range - sticking the 6cents in water gives lower values than what I get from rain events
It is relativley easy to make your own sensor by etching a thin ds pcb.
A simple resistive sensor has the wrong footprint for a reliable capacitive sensor
This may fit the bill, i think all the car ones are optical.
Look up the Kelvin water-drop generator but don't build one. Just notice how the water drops take energy through induction from the charged loop they pass through.
The more rain that falls through the loop, the more change. There's probably a circuit that will hold a voltage dependent on how many drops pass through over time.
