I found some similar circuits but aren't good enough for me. Some circuits measure the water's resistance to determine the level. That is dangerous for drinking water (contamination) or explosive liquids because electricity is in contact with water. The Pressure sensor have a tube. The tube end on the botton of the tank. When the liquid fill the tank, the pressure inside the tube increase. The 12F675 have A/D converters. The PIC measure the pressure and light up the led corresponding to the liquid level. Green LED = Full, Yellow = Half, Red = Almost Empty. When the tank is completely empty, It turn on the Water pump or activate the buzzer.
Click here to download the full size of the above Circuit.
Before using the circuit, you have to calibrate it. First, start filling the thank (just one or two inches) and press the switch on the RED led (Empty). Fill the thank to the half and press the switch on the YELLOW led. Finally, when the tank is full, press the swith on the GREEN led. The water pump will stop. When the tank is almost empty the PIC will turn on the pump until the liquiq level reach the top. USE ANY RESISTIVE PRESSURE SENSOR, JUST CHECK THE SENSOR WORKS WITH 5 Volts.
Update: I found that washer machines uses this method to determine the water level, however, the pressure sensor in a washer machine is not a resistive one, is just a switch.
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is....
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to....
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This....
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the....
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound,....
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the....
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power....
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
characters left: