Ultrasonic level gauge

The ultrasonic level gauge can adopt two-wire, three-wire or four-wire technology. The two-wire system is: power supply and signal output are shared; the three-wire system is: power supply circuit and signal output circuit are independent. When using DC 24v power supply, one can be used 3-core cable, the negative end of the power supply and the negative end of the signal output share one core wire; the four-wire system is: when using AC 220v power supply, or when using DC 24v power supply, the power supply circuit and the signal output circuit are required to be completely isolated. Use a 4-core cable. DC or AC power supply, 4~20mADC, high and low switch output.

       working principle

       The working principle of the ultrasonic level meter is that the ultrasonic transducer (probe) sends out a high-frequency pulse sound wave when it encounters the surface of the measured level (material), is reflected, and the reflected echo is received by the transducer and converted into an electrical signal. The propagation time of the sound wave. It is proportional to the distance from the sound wave to the surface of the object. The relationship between the sound wave transmission distance S and the sound speed C and the sound transmission time T can be expressed by the formula: S=C×T/2.

       The probe part emits ultrasonic waves, and then is reflected by the liquid surface, and the probe part receives it again. The distance from the probe to the liquid (object) surface is proportional to the elapsed time of the ultrasonic wave:

       hb = CT2 i.e.

       Distance [m] = time × speed of sound/2 [m]

       The temperature compensation formula of the speed of sound: LU20 ultrasonic level gauge ambient sound speed = 331.5 + 0.6 × temperature

       Site conditions

       Ambient temperature: -10 ~ +60℃ (special instructions are required for low temperature conditions)

       Case protection grade: IP65 suitable for outdoor installation

       Applicable measurement medium: Suitable for most liquid and powdery granular solids, weak acids, weak bases, strong bases, and strong acids below 40%. If in strong acid applications, please contact our company and use anti-corrosion probes.

       Vessel pressure: 0.7~3 bar

       In any of the following situations, pay attention:

       Liquid/solid with foam

       There are strong voltage, strong current, strong electromagnetic interference around, try to avoid high voltage, high current and strong electromagnetic interference

       Strong wind and direct sun

       Strong vibration

       The ultrasonic level meter is a digital level meter controlled by a microprocessor. In the measurement, the pulsed ultrasonic wave is emitted by the sensor (transducer), and the sound wave is reflected by the surface of the object and then received by the same sensor and converted into an electrical signal. The distance between the sensor and the object to be measured is calculated from the time between the emission and reception of the sound wave. Due to the non-contact measurement, the measured medium is almost unlimited, and it can be widely used for height measurement of various liquids and solid materials.

       Features

       Multi-pulse low-voltage multi-point transmitting and transmitting circuit, double-balanced noise suppression multi-point receiving circuit (QF-9000 series): Improve the reliability of the instrument, solve the problem of inaccurate measurement of uneven level, and greatly enhance the anti-interference ability. Work stably near the transmission tower of the substation.

       Automatic power adjustment, gain control, temperature compensation.

       Advanced detection technology and rich software functions adapt to various complex environments.

       Using new waveform calculation technology to improve the measurement accuracy of the instrument.

       The suppression function of interference echo ensures the authenticity of the measurement data.

       16-bit D/A conversion to improve the accuracy and resolution of current output.

       The sensor is made of tetrafluoroethylene, which can be used in various corrosive occasions.

       Multiple output forms: programmable relay output, high-precision 4-20mA current output, Rs-485 digital communication output