Equipment Composition

二、Equipment Principle

Portable (handheld) Doppler ultrasonic open channel flowmeter is the use of sound waves in the fluid propagation of the Doppler effect, by measuring the moving particles in the fluid scattering acoustic wave Doppler shift to get the speed of the fluid, combined with the built-in pressure type water level meter, the use of velocity area method, you can measure the flow of liquid.

Upper computer memory space up to 16M, can store more than 100,000 data, built-in high-performance lithium battery, a charge can work for more than 12 hours, equipped with a liquid crystal display, can display real-time flow rate, water level, flow and other data.

Average flow rate measurement:

The measurement of flow rate is obtained by transmitting and receiving ultrasonic signals through ultrasonic probes (transducers) and doing corresponding calculation and processing: Transducer 1 transmits ultrasonic signals with frequency f1 from underwater to surface at a certain Angle. After touching suspended particles or bubbles in water, the frequency is offset and reflected to transducer 2 at the frequency f2, which is the Doppler will, and the difference between f2 and f1 is the Doppler frequency difference fd. Let the fluid flow rate be v, the ultrasonic velocity be c, and the Doppler shift fd be proportional to the fluid flow rate v. There will be a large number of impurity particles and bubbles in water, each reflecting particle corresponds to a Doppler shift fd, and its flow rate can be obtained by conversion, and the average flow rate of these large numbers of particles is also the average flow rate of the fluid.

三、Applied Range

四、Equipment Installation

五、Features

1、Measure the flow rate of non-full tube (round tube, egg tube or other shaped tube);

2、Measure the flow of channels (round channels, rectangular channels or other special-shaped channels);

3、Natural river and stream volume can be measured;

4、Measurement of sewage discharge channels or pipes (sewers) flow;

5、 Provide instantaneous flow value and cumulative flow value;

6、Instrument built-in data memory;

7、The sensor can work for a long time under harsh on-site and sewage water quality;

六、Technical Specification

Measurement principle: Doppler effect, velocity area method 1. Flow measurement range: 0.02-5m/s (can be expanded) Flow measurement accuracy: ±1%±0.01m/s resolution: 1mm/s 2. Water level measurement range 0-10m (can be expanded) Water level measurement accuracy: ±25px resolution: 1mm 3. Flow measurement range: 0.001-9999999m3 /h Flow measurement accuracy: ±2-3% (depending on the section shape) Resolution: 0.001m3/h 4. Temperature measurement range: -20-65℃ Temperature measurement accuracy: ±0.5℃ Resolution: 0.1℃ 5. Power consumption: ≤1W 6. Data refresh frequency: 1HZ 7. Built-in battery: 3.7V 5AH Charging power: 5V 1A 8. Display: 256 x 128 9. Port: RS485 Modbus 10. Storage capacity: 16M (extensible) 11. Probe material: ABS 12. Probe protection level: IP68 13. Working temperature: -20-65℃ (water does not freeze) 14. Measuring rod: 1m/ root (can be spliced) 15. Standard 20 meters special cable 1 (assembled, not removable, not cut) 16. Portable measuring rod 1 m / 2 (separately packaged accessories)