Ultrasonic Doppler Flow Meter for River and Open Channel
Introduction
KDF1000 series flow meter is a product that measures the velocity
and flow of water in natural waters, channels, or pipelines.
The flow meter is divided into two parts: the sensor and the host,
which are connected by a cable.
It can measure the speed and flow of water in channels and rivers,
and the water level is more than 20 cm higher than the top of the
sensor.
It can measure the speed and flow of water in pipes and culverts.
The water level must be more than 20 cm higher than the top of the
sensor, and the inner diameter of the pipe must be ≥ 500 mm.
Principle
The sensor has two transducers, one transmitting and one receiving.
When the sensor is facing the direction of water flow, that is,
under the premise of reverse flow measurement:
1. When the water is still, the received frequency is the same as
the transmitted frequency.
2. The faster the flow rate, the faster the frequency received by
the receiving sensor, which will be higher than the transmitting
frequency.
3. The slower the flow rate, the slower the frequency received by
the receiving sensor, but it will be higher than the transmitting
frequency.
When the sensor measures along the direction of water flow:
1. When the water is still, the received frequency is the same as
the transmitted frequency.
2. The faster the flow rate, the faster the frequency received by
the receiving sensor, but it will be lower than the transmitted
frequency.
3. The slower the flow rate, the slower the frequency received by
the receiving sensor, but it will be lower than the transmitting
frequency.
From the above, the water flow velocity and direction can be
calculated.
The sensor must be directly facing the direction of water flow
during installation and use.
Parameters
| Structure | split type; |
| Measurement Types | velocity, flow, water depth, water temperature |
| Protection Level | IP68 |
| Purpose | online measurement |
| Velocity Measurement Range | standard configuration is 0.03m/s～5.00m/s (water depth above
sensor: 20cm); Other flow rate ranges can be customized. |
| Flow Rate Measurement Resolution | 1mm/s; |
| Flow Velocity Measurement Accuracy | ±2～4% of measured flow velocity; |
| Water Depth Measurement | 0.02m～10.00m; |
| Resolution | 2mm |
| Accuracy | ±0.5%; |
| Temperature Range | 0～60ºC; |
| Resolution | 0.1ºC; |
| Flow Rate Range | 10 liters/sec～99999999 cubic meters/hour |
| Power Supply | battery powered, 12VDC; |
| Output Signal (Battery Powered) | RS485; |
| RS485 Output Signal Content | flow rate, instantaneous flow, cumulative flow, water level,
temperature |
| Output Signal (External Power Supply) | 4-20mA; |
| 4-20ma Output Signal Content | instantaneous flow |
| Wireless Transmission Function | optional accessories, data transmission to the background server
software via mobile GPRS. Need the customer has a server with a
fixed IP address, or a leased cloud server. |
| Cable Length Between Sensor and Transmitter | 10 meters; |
| Types of Tested Waterways | pipes, channels, natural streams, rivers; |
| Liquid Ph Requirements | PH value between 6-8, non-corrosive to the sensor. |
| Liquid Temperature Requirement | 0～50℃ |
| Liquid Pressure Requirement | 1 standard atmospheric pressure in natural environment |
| Power Supply for The Flowmeter | 11～14VDC, current is 250mA. |
| Continuous Working Power Consumption | 14V×250ma=14V×0.25A=3.50W. |
Application
