Ultrasonic level meter is an instrument used to measure the level of liquid or solid materials. Its structure usually includes the following main parts:
1. Ultrasonic transmitter: This is the core component of the level meter, which is used to generate and transmit ultrasonic pulses. The transmitter is usually made of piezoelectric crystal material, which will generate mechanical vibration when voltage is applied, thereby emitting ultrasonic waves.
2. Ultrasonic receiver: Located in the same component as the transmitter, it is used to receive ultrasonic signals reflected from the liquid surface. The receiver also uses piezoelectric crystals, which will generate electrical signals when receiving reflected waves.
3. Processing unit: It includes signal processing and control circuits. The processing unit receives the signal from the receiver, calculates the time difference (i.e. flight time) from the emission of ultrasonic waves to the reception of reflected signals, and calculates the liquid level height based on this time difference and the propagation speed of ultrasonic waves in the air.
4. Display and output unit: The processing unit converts the calculated liquid level height into a digital or graphical form that can be displayed and displays it through the display. At the same time, the liquid level signal can also be output to the control system or other external devices in analog or digital form.
5. Housing and mounting accessories: All components of the ultrasonic level meter are enclosed in a housing, which is usually waterproof, dustproof and corrosion-resistant. The mounting accessories are used to fix the level meter at the measurement location, such as the top of the tank or the wall of the tank.
Specifically, the working principle of the ultrasonic level meter is that the ultrasonic transmitter emits ultrasonic pulses downward, and the pulses are reflected back after encountering the liquid surface and received by the receiver. The processing unit calculates the liquid level height by measuring the time difference between transmission and reception. This measurement method does not require contact with the liquid and is suitable for level measurement of various liquids and certain solid materials. It has the advantages of easy installation, simple maintenance and high measurement accuracy.