Liquid Level Computing and Storage Device

Project Cost: 4,800

Project Code: 1178

Description of the project:

This project is used to measure the water level in a dam, after a particular time interval and to store them in a memory IC for the sake of records. Later a person can access the memory using this project and see the previous records using a keypad and LCD. This data can be sent to a computer through a serial port.

Block Diagram of Liquid Level Computing and Storage Device:

You will get the following documents with this project:

1. Project Report in pdf format and in doc (word) format
2. Circuit diagram
3. PCB layout
4. Microcontroller program in assembly language
5. Hex file of the microcontroller code
6. Datasheets of all the components / ICs used in the project

Project Photographs:

Description in detail:

This project stood apart from the list of projects based on sensors. And this project mainly consists of the following blocks:

1. Potentiometer and pulley arrangement: We have to measure the water level, for this purpose we are going to use a pulley-float/potentiometer arrangement. Pulley will be hanged above the water and a float will be resting on the water’s surface using a rope. And potentiometer will be fixed at the center of the pulley. So as the water level goes up and down, respectively pulley and potentiometer will rotate. So eventually water level is converted into the resistance of the potentiometer. A constant current source is used to pass current through this potentiometer, so as to get a voltage drop. This voltage is given to the amplifier.
2. Amplifier: As the voltage output of the potentiometer is less, it has to be increased to the 0 to 5 volts range. We are going to use a linear amplifier for this purpose.
3. Voltage to frequency converter: The main part of our project is microcontroller (89s51) which reads only digital input (0V & 5V) But the output of Amplifier is in analog form, so it has to be converted into digital format, for this purpose we are going to use Voltage to Frequency converter to convert analog output from amplifier into the digital output to be given to microcontroller
4. EEPROM: We are going to use AT12c02 as an EEPROM memory, it is Electrically erasable programmable read only memory. Microcontroller communicates with E2Prom using I2C bus protocol. It stores the data even if the power supply is disconnected. This is used to store the water level along with date and time when it is recorded.
5. LCD: 16×2 alphanumeric Liquid Crystal Display (LCD) is used. It can display alphabets along with numbers on 2 lines each containing 16 characters.
6. PC Interfacing: We are going to use max 232 IC for PC interfacing, the values of temperature and light will be sent to PC when the key is pressed
7. Keypad: Various operations of keypad are: I. Display current level II. Display current flow III. Display previous records IV. Erase previous records V. Send data to Computer VI. Set logging time VII. Set current time

8051 Microcontroller in this project

The microcontroller is the CPU (central processing unit) of our project. We are going to use 89s51 because it belongs to the 8051 microcontroller family. The various functions of the microcontroller are like:

• Reading the digital input from Volt to Freq converter which is derived from Potentiometer and pulley arrangement
• Sending this data to LCD so that the person operating this project should read the values of the Water level.
• Storing the data into EEPROM memory and displaying it later using keypad IV. Sending the values of temperature and light to the computer using a serial port

Applications and Advantages:

1. This can be used at water dams to measure the water level.
2. This project can also be used in Industries

Future Development:

1. We can implement SMS technology into this project

Video of the project: Liquid Level Computing and Storage Device

Youtube video coming soon

Question: Which type of memory you have used and what is the size of the memory?

Answer: We have used EEPROM memory and the size is 64kb. You can increase the size up to 512kb if you want.