Doppler Flow Meter

1.Doppler Flow Meter product principle

Doppler Flow Meter uses the Doppler effect to measure the flow rate of liquids and is installed 20CM below the lowest water level to avoid being exposed to water.In the field of acoustics, when there is relative movement between the sound source and the receiver (i.e., the probe and the reflector), the frequency of the echo will change.This frequency change is called frequency shift, that is, the Doppler effect.The frequency of the sound wave becomes higher when moving towards the observer and lower when moving away from the observer.Doppler Flow Meter calculates the flow rate by calculating frequency changes.

2.Doppler Flow Meter technical parameters

1.Power supply: DC10-15V

2.Working current: 80-180mA 12V

3.Sound wave frequency: 2MHZ

4.Blind spot: 6.5-7 cm (the water level is lower than the blind spot measurement data has low accuracy)

5.Flow rate range: 0m~+6m/s,

6.Accuracy: ±1.0%±1cm/s

7.Water level: Range: 0.03m~5m (customizable 10m), accuracy: 0.3%±0.5cm

8.Water temperature: range: -10℃~60℃, accuracy: ±1℃

9.Instantaneous flow range: 0～99.99m³/s

10.Cumulative flow range: 0.1m³～99999m³

3.Doppler Flow Meter installation instructions

Normal installation ensures 20CM below the minimum water level to avoid exposing the water

Sensor installation diagram:

4.Doppler Flow Meter Notes

1.The sensor needs to avoid silt and collisions of objects such as gravels.Where there are many aquatic plants, grilles need to be installed to prevent aquatic plants from entangling.

2.Sensor installation direction, the sensor transmission surface needs to be installed in the flow direction.

3.The sensor has a sound wave blind spot.Try to ensure that the sensor is below 20 cm underwater (the sensor is semi-exposed under water or blocked by sludge may appear false data, with very low probability.Usually, the data will appear large numbers such as more than 2 meters/second.It is recommended that secondary developers use sensors to block the large flow rate value by the water level, or the water flow rate is not that large in actual application scenarios, which can directly block the flow rate greater than 2 meters or more).

4.The cable vent pipe is not difficult to break, affecting the water level measurement.

5.Try to do a good job in signal and power lightning protection.

6.If the sensor cable is connected to a length, you need to add a 485 relay, and the power supply avoids the interference of the inverter.