Ultrasonic Liquid Level Sensor-Ppt[1]

Ultrasonic Liquid Level Sensor

Done By

Veliyath Nazeem Shiyas

Introduction

Scenario:To monitor the level of corrosive liquid, which is

stored in a huge tank periodically, and to draw as well as to fill the tank.

Existing System:• Use mechanical devices & timers.• As the liquid is corrosive, its very different to maintain

the current system, which is having direct contact with the liquid.

• Can’t ensure safety of the operators.

Contd…

Proposed System: • A safer system in Chemical handling.• Includes an ultrasonic level sensor and an optional

Stepper motor controller. (Stepper motor controller not yet added due to cost concerns).

• Level sensor detects the level of chemical and displays its distance in centimeters.

• Can add stepper motor to ON or OFF valves to control the levels.

Principle Of Operation

• Consists of basically a transmitter receiver arrangement working in ultrasonic frequency.

• Transmitter sends an ultrasonic pulse of required frequency and the detector detects the same pulse, which gets reflected back from the liquid surface.

• Timer in the circuit would monitor the time delay between transmission and detection from which the distance can be calculated – logic circuits display it.

Block Diagram

This level controller consists of stepper motors and controllers. I haven’t included it (This is for the future expansion)

Circuit Diagram

Circuit Explanation

• Receiver Section

Contd..

• Detection Circuit

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• Signal Detector

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• Signal Holding Circuit

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• Transmitter Circuit

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• Temperature revision voltage generating circuit

Contd..

• Resonator

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• Power Supply Circuit

Parts

• Ultrasonic Sensor• Microcontroller (PIC16f876)• Low Noise Operational Amplifiers(LM833N)• Low Power Operational Amplifiers(LM358)• NAND Gates(4011B)• Inverters(4069UB)• Three terminal voltage regulator for +5V (7805)• Transmitter drive transistor (2SC1815)• Schottky Barrier Diode (ISS106)• LCD Display• Precision Centigrade Temperature Sensors

Flow Chart

Snapshots Of Project & Development

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Conclusion and Scope

• It enables safe chemical handling• It makes operator risk free• The system makes chemical handling easy and optimized.• The system is very compact, so that it can be fitted easily• The system is less expensive, so that it is affordable by any

companies• The system has temperature sensor circuit, so that it works

under all temperatures, error free.• It is an auxiliary system, so that won’t create any difficulty for

the normal operation.

Future Enhancements

• It can be added with sound alert system • It can be added with LEDS with multiple colors• It can be added with a remote display to the management• A stepper motor and control circuit can be added with this circuit

to control the valves• A solenoid relay circuits can be added with this level sensor to

open and close the valves which control the liquid level• Now we provide 9V DC power supply externally. An integrated

power supply can be provided.• It can be added with wall mountings / hooks or a holder as per

requirement.• Pump controllers can be added with this level sensor to maintain

the liquid level in the tank.

References

• Sergio Franco, Design with Operational amplifier and analog integrated circuits, Tata Mc Graw Hill

• John B Peatman, Design with PIC Micro controller, Pearson Education.

• Thomas L Floyd, Electronic devices, Pearson Education

• www.discovercircuits.com• www.nicera.com• www.microchip.com• www.national.com• www.datasheetarchieve.com•

http://www.warburtech.com/microcontrollers/28.pin.pic.microcontrollers/pic16f876.microcontroller.htm

• http://ww1.microchip.com/downloads/en/DeviceDoc/30292c.pdf• http://www.techdesign.be/projects/008/008.htm

Thank You!!