09-04-2011, 02:13 PM
submitted by-
DHARMENDRA KUMAR MISHRA
ultrasonic sensor.ppt (Size: 194 KB / Downloads: 265)
INTRODUCTION
Ultrasonic sensors (also known as transceivers when they both send and receive) work on a principle similar to radar or sonar which evaluate attributes of a target by interpreting the echoes from radio or sound waves respectively
What is Sensor or Transducer
• An ultrasonic transducer is a device that converts energy into ultrasound, or sound waves above the normal range of human hearing.
Construction
• Ultrasonic Level Sensor is consist of two main parts .
• Transmitter
• Receiver
WORKING
This sensor provides very fast and reliable data output. Whole answer is mainly dependent upon time delay or lag. The ultrasonic sound is created by the Piezoelectric crystal inside the sensor. It converts electrical energy to ultrasonic sound energy.
Advantages
1. Non disturbing technique.
2. Can be used for wide range of things like solid and liquids with wide range of viscosity.
3. Low price.
4. High functionality.
5. Very accurate and low error.
6. Long life instrument.
7. Can measure the level of different liquids having different densities in same tank
Limitations
• 1. Sensor mounting must be properly done.
• 2. Tank should be free from obstacles otherwise it may cause error in measurement.
• 3. Result may get affected due to change in temperature or pressure inside the tank or container
Applications
• Automatic pump control.
• Flow measurement.
• open channel flow measurement.
• Used in water/waste applications.