Generally, water stored in overhead tank is wasted due to over flow , when the tank is full. Water level alarm using micro-controllers like 8051 and AVR are shown in previous articles . This article shows simple circuits of water level indicator.
- BC548 transistors-Q1, Q2, Q3, Q4
- Resistors R1, R2, R3, R4 (2.2 k ohms)
- R5, R6, R7 (100 ohm)
- Led – Red (LED3) , Green(LED1) , Yellow(LED2)
- Metal Contacts – M1, M2, M3, M4.
- The circuit is designed to indicate three levels of water stored in the tank: low but not empty, half and full but not overflowing.
- When there is no water in the tank, all the LEDs are off as an indication that the tank is completely empty.
- When water level increases and reaches M2, the contacts M1 and M2 get shorted as water acts as a conducting medium between M1 and M2.
- This will turn on the transistor Q1 and the Green LED starts to glow. As the water level continues to rise and reaches half the tank, M3 will come into contact with water and receives a small voltage from M1.
- As a result, Q2 is turned on and Yellow LED will glow. When the water in the tank rises to full tank, M4 is also shorted with M1 and both Q3 and Q4 will turn on.
- The Red LED glows and also an alarm is made by the buzzer as an indication that the tank is full and the water pump or motor can be turned off.
- Water Level Indicator Is Very Useful In Houses.
- This Projects is also implement at large scale like ,school ,collages , Universities, Malls, Multinational ,International Companies as well.
- It Helps Us To Save Our Electricity And Also Help To Prevent Of Water Wastage.