1 measurement principle
principle
The working principle of ultrasonic level meter is that the high-frequency ultrasonic pulse sent by the transducer (probe) meets the surface of the measured medium and reflects back, and some of the reflected echoes are received by the same transducer and converted into electrical signals. Ultrasonic pulse propagates at the speed of sound waves, and the time interval from transmission to reception is directly proportional to the distance from the transducer to the surface of the measured medium. The relationship between the distance value S and the speed of sound C and the transmission time T can be expressed by the formula: S=CxT/2.
Because the transmitted ultrasonic pulse has a certain width, the reflected wave and the transmitted wave overlap in a short area near the transducer, which makes it impossible to identify and measure its distance. This area is called the measurement blind area. The size of blind area is related to the model of ultrasonic level gauge.
trait
Due to the advanced microprocessor and unique EchoDiscovery echo processing technology, ultrasonic level gauge can be applied to various complex working conditions. The sensor has a built-in temperature sensor, which can realize the temperature compensation of the measured value.
The ultrasonic transducer adopts the patented technology of the best acoustic matching, so that its emission power can be radiated more effectively, and the signal strength can be improved, thus achieving accurate measurement.
Installation requirements of ultrasonic level gauge/level gauge.
Installation requirements:
When the transducer emits ultrasonic pulses, it has a certain emission angle. From the lower edge of the transducer to the surface of the measured medium, there must be no obstacles in the area radiated by the emitted ultrasonic beam, so the facilities in the tank, such as ladders, limit switches, heating equipment and supports, should be avoided as far as possible during installation. Furthermore, it should be noted that the ultrasonic beam must not intersect with the feed stream.
Attention should also be paid when installing the instrument: the highest material level should not enter the measurement blind area; The instrument must keep a certain distance from the tank wall; The instrument shall be installed so that the emission direction of the sensor is perpendicular to the liquid level as much as possible.