1. 9 LEVEL OVERHEAD WATER TANK NDICATOR
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2. ABSTRACT
This is the circuit designed for overhead tank digital water level indicator.
It is built around priority encoder, BCD-to-7-segment decoder, 7-segment display and a few discrete components.
Due to high input impedance, priority encoder senses water in the container from its nine input terminals.
The inputs are connected to +5V.
The ground terminal of the sensor must be kept at the bottom of the container (tank).

3. PROJECT BLOCK DIAGRAM

4. HARDWARE REQUIREMENTS
POWER SUPPLY BLOCK
74HC147
CD4511
TRANSISTOR
7-SEGMENT DISPLAY
LED
1N4007
RESISTOR
CAPACITOR

5. POWER SUPPLY Bridge rectifier 5v Regulator 230 V AC 50 Hz 5V DC
Filter(470µf)
12V step down
transformer

6. 10-TO-3 LINE PRIORITY ENCODER (74HC147)
The 74HC/HCT147 are high-speed Si-gate CMOS devices
and are pin compatible with low power Schottky TTL
(LSTTL).
The devices provide the 10-line to 3-line priority encoding
function by use of the implied decimal “zero”. The “zero”
is encoded when all nine data inputs are HIGH, forcing all
four outputs HIGH.
The 74HC/HCT147 9-input priority encoders accept data
from nine active LOW inputs (A0 to A8) and provide a
binary representation on the four active LOW outputs (Y0
to Y3).

7. FEATURES Encodes 10-line decimal to 3-line BCD
Useful for 10-position switch encoding
Used in code converters and generators
Output capability: standard
ICC category: MSI
Functional Diagram

8. BCD-TO-7 SEGMENT DECODER/DRIVER (CD4511)
The CD4511BC BCD-to-seven segment latch/decoder/ driver is constructed with complementary MOS (CMOS) enhancement mode devices and NPN bipolar output drivers in a single monolithic structure.
The circuit provides the functions of a 3-bit storage latch, an 8321 BCD-to-seven segment decoder, and an output drive capability.
It can be used with seven-segment light emitting diodes (LED), incandescent, fluorescent, gas discharge, or liquid crystal readouts either directly or indirectly.

9. FEATURES
Low logic circuit power dissipation
High current sourcing outputs (up to 25 mA)
Latch storage of code
Blanking input
Lamp test provision
Readout blanking on all illegal input
combinations
Lamp intensity modulation capability
Time share (multiplexing) facility
Equivalent to Motorola MC13511

10. BC547 The BC547 transistor is an NPN Epitaxial Silicon Transistor.
The BC547 transistor is a general-purpose transistor in small plastic packages.
It is used in general-purpose switching and amplification BC847/BC547 series 45 V, 100 mA NPN general-purpose transistors.
Whenever base is high, then current starts flowing through base and emitter and after that only current will pass from collector to emitter

11. Resistor
Resistor is a two terminal passive electrical component that implements electrical resistance as a circuit element.
Resistors limits or regulate the flow of electrical current in an electronic circuit.
Resistors are available in a range of different resistance values which are used as per the requirement.

12. Capacitor
Capacitor is a two terminal passive electrical component used to store the electrical energy electrostatically in an electrical field
Capacitors are two types electrolytic and ceramic.
Ceramic capacitors are unpolarized. These capacitors have negligible internal inductance or resistance.
Electrolytic capacitors are polarized and if connected backwards are likely to explode.

13. 1N4007
Diodes are used to convert AC into DC these are used as half wave rectifier or full wave rectifier. Three points must he kept in mind while using any type of diode.

14. LED LEDs are semiconductor devices are made out of silicon
When current passes through the LED, it emits photons as a byproduct. Normal light bulbs produce light by heating a metal filament until its white hot
LEDs present many advantages over traditional light sources including lower energy consumption, longer lifetime, improved robustness, smaller size and faster switching

15. BIBILOGRAPHY www.beyondlogic.org www.wikipedia.org

16. QUERIES ?

17. THANKYOU