Wireless Tank Level Monitor

thingiverse

This is a wireless tank level monitor that was hastily put together for monitoring our home rainwater tank's water level, which is approximately 60 meters up the hill from the house. It operates on two Arduino Pro Mini boards and utilizes an ultrasonic sensor to detect the water level. The components are extremely affordable and were a fun project to assemble. It consists of a solar-powered transmitter situated atop the water tank, which senses the water level and converts it into a percentage full reading. This information is then transmitted to a handheld receiver, which displays the water level percentage when the button is pressed. The battery holders used are 4xAA and 4xAAA flex holders. You will need: 2 x Arduino Pro Mini boards (available on eBay for approximately $10 each) An ultrasonic sensor (available on eBay for approximately $5) A transmitter and receiver module (available on eBay for approximately $15) 2 x Buck converters (available on eBay for approximately $5 each) A 16x2 LCD display (available on eBay for approximately $10) A 10k trim pot and a 220k resistor A 99mm x 89mm 6v solar panel Some strip board or veroboard or protoboard to assemble the components The transmitter is relatively straightforward. The Trigger pin of the HC-SR04 goes to pin 10 of the Pro Mini, while the Echo pin goes to pin 9. The data pin of the radio transmitter goes to pin 12 of the Pro Mini. All power is routed through a Buck converter set to 5v to the Pro Mini, HC-SR04, and radio transmitter. The Buck converter is used because the HC-SR04 reportedly has a maximum voltage of 5.5v, so it's best to run everything off the Buck. I also added a 99mm x 89mm 6v solar panel that I already had on hand. If you cannot find one this size, either design your own mount or let me know the dimensions and I will draw one for you. Female header pins are used under the Pro Mini so it can be easily removed for uploading sketches. You will need to download the radiohead library for the Arduino IDE before you can upload the sketches. The receiver is a bit more complicated but still easy to understand. Just look at the jpg of the veroboard layout for how I put it together. I used 4 x AAA batteries for the RX and added a momentary push button switch on the battery +. Simply press and hold the button until the Pro Mini boots, and you will get a reading. Of course, you are welcome to make any changes as this is just one possible configuration, and may not suit your specific needs.