Doppler Flowmeter

Product Manual

The AN-HWDF-PN01 Doppler flowmeter is designed for flow velocity and flow measurement in rivers, open channels, pipelines and other working conditions. Adopting ultrasonic detection technology, it features high measurement accuracy, excellent stability and low susceptibility to environmental interference. With no rotating parts, it requires minimal maintenance and delivers high operational reliability. It is an ideal choice for both online monitoring and portable flow measurement applications.

When relative motion exists between an ultrasonic transmitter and a receiver, the frequency of the received ultrasonic signal will differ from the original transmitting frequency. Tiny solid particles and air bubbles moving along with water will cause frequency shift of the signal received by the ultrasonic transducer, and the shift increases with the flow velocity of suspended substances in water. The system calculates water flow velocity based on the measured Doppler frequency shift, then multiplies the velocity by the cross-sectional area of the channel to obtain flow rate.

Since the propagation speed of sound in water is closely related to water temperature, a built-in temperature sensor is equipped to measure water temperature and calibrate acoustic velocity. A diffused silicon pressure sensor is adopted to detect water depth, namely the vertical distance between the sensor and the water surface.

n Compact streamline design with small flow-facing area, bringing negligible impact on flow regime.

n Supports Modbus protocol and RS485 bus communication.

n Free of mechanical rotating components, avoiding blockage by sediment or entanglement by water weeds and debris.

n Fully electronic structure, wide input voltage range and low power consumption.

n Precise and stable measurement, high reliability and strong anti-interference capability.

n Wide application range, applicable to various water environments from tap water to river water with high sediment content.

Measured Parameters：Flow velocity, water level, water temperature, instantaneous flow, cumulative flow

Measurement Mode：Continuous online monitoring

Measuring Principle：Flow velocity：Acoustic Doppler method;Water level：Hydrostatic pressure method;Flow rate：Velocity-area method

Forward Flow Velocity：Range：0.021 m/s ～ 6.00 m/s

Resolution：0.001 m/s

Accuracy：≤±1.0% ±1 cm/s

Reverse Flow Velocity (Optional)：Range：-6.000 m/s ～ -0.021 m/s

Resolution：0.001 m/s

Accuracy：≤±1.0% ±1 cm/s

Water Level：Range：0.03 m ～ 10 m (Customizable)

Resolution：0.001 m

Accuracy：±0.25%FS

Repeatability Error：≤±0.2 cm

Hysteresis：＜±0.1 cm

Water Temperature：Range：-10 ℃ ～ 80 ℃

Resolution：0.1 ℃

Accuracy：±0.5 ℃

Transmitting Frequency：2 MHz

Instantaneous Flow Range：0 m³/s ～ 9999 m³/s

Cumulative Flow Range：0 m³ ～ 999,999,999 m³

Operating Voltage：DC 6.8 V ～ 24 V

Average Current (@ DC 12V)：Working mode：≤45 mA

Sleep mode：≤6 mA

Response Time：1 s

Stabilization Time：7 s

Valid Working Water Depth：0 m ～ 10 m

Data Refresh Cycle：6 s ～ 60 s (Adjustable)

Transmitter Beam Angle：5°

Spectrum Output：Supported, maximum 512 sampling points

Compensation Function：Configurable velocity compensation & pressure compensation

Output Signal：Modbus RS485

Protection Grade：IP68

Anti-Corrosion Grade：Grade 10

ESD Immunity：Class 3

Surge Immunity：Class 4

Housing Material：ABS polymer material

Standard Cable：10 m air-guided anti-corrosion cable (Custom length available)

Working Liquid Pressure：1 standard atmospheric pressure (ambient condition)

MTBF：＞25000 h

Overall Dimension：173 × 50 × 29 mm

Storage Temperature：-40 ℃ ～ 80 ℃

Operating Temperature：-10 ℃ ～ 60 ℃

Weight：0.8 kg (Including 10 m cable)