Liquid/Water Level Indicator with Alarm using 8051 Microcontroller (AT89C51)
This article illustrates the construction and working of a liquid/water level indicator. Such an indicator is used in tanks to indicate the level of liquids and alert us when the tank is full. So by this circuit we can monitor the various levels of the tank and can avoid spillage of water and also we can configure our supplies according to the various levels of tank. Such module or circuit can be installed in big buildings where manual monitor of tanks is difficult and its indicator can be placed at some centralised place.
This water level indicator circuit works on the principle that water conducts electricity. A wire connected to VCC and four other wires are dipped in tank at different levels namely quarter, half, three-fourth, full and their output are taken on pins P3.0, P3.1, P3.2, P3.3 via a transistor BC547. Port P2 is connected to data pins of LCD and P1.0, P1.1, P1.2 are respectively connected to RS, RW, and EN pins of LCD.
Initially when the tank is empty LCD will show the message VACANT. As the tank starts filling up wire at different levels get some positive voltage, due to conducting nature of water. This voltage is then fed to their corresponding pins on controller. When level reaches to quarter level, LCD displays the message QUARTER. On further rise of level, HALF and 3/4 QUARTER are displayed on LCD. When tank gets full LCD shows the message FULL CLOSE TAP. A buzzer is also provided to produce a alert the user when the tank gets filled. This buzzer can be made off by pressing the switch connected between pin 15 of controller and VCC.
A preset is a three legged electronic component which can be made to offer varying resistance in a circuit. The resistance is varied by adjusting the rotary control over it. The adjustment can be done by using a small screw driver or...
BC547 is an NPN bi-polar junction transistor. A transistor, stands for transfer of resistance, is commonly used to amplify current. A small current at its base controls a larger current...
The piezo buzzer produces sound based on reverse of the piezoelectric effect. The generation of pressure variation or strain by the application of electric potential across a piezoelectric material is the underlying...
LCD (Liquid Crystal Display) screen is an electronic display module and find a wide range of applications. A 16x2 LCD display is very basic module and is very commonly used in various devices and circuits. These modules are preferred over seven segments...
Free Circuit Design & Simulation Tool by TI
WEBENCH Design Environments are unique and powerful software tools that deliver customized power, lighting, filtering, clocking and sensing designs in seconds. These easy-to-use tools help you generate, optimize and simulate designs that conform to your unique specifications. They allow you to make value-based tradeoffs at a design, system and supply chain level before your design is committed to production.
Design & Simulation Tools
Sensors, Filter, Clock and Amplifier Design
Download Tools, Models and Symbols