Ultrasonic
Doppler flow meter
The HKI 306 ultrasonic Doppler flow meter is explosion-proof and widely used on rivers, open channels, and pipes. Ultrasonic sensing is accurate and stable, with little environmental drift, no moving parts, low maintenance, and high reliability for both online and portable work.
Ultrasonic flow, one probe
Acoustic Doppler velocity and velocity-area flow — zero dead band, no head loss, no moving parts. Submerge and measure, including reverse flow. Open channel and pipe, full or partial, Class 10 corrosion resistance, explosion-proof and intrinsically safe.
Three-in-one · direct flow output
Measures velocity, depth, and temperature together, with an embedded flow model, Direct instantaneous and totalized flow.
Slim hydrofoil · compact
Streamlined and compact (Only 3 cm high), small projected area, little effect on the flow.
Temperature-compensated sound speed · bidirectional velocity
Built-in temperature sensor, Compensates water temperature effects on sound speed, measures forward and reverse velocity.
Ultrasonic Doppler velocity
Uses acoustic Doppler for velocity, High accuracy, stable data, strong real-time performance.
Zero dead band · works at low level
Zero-dead-band measurement, Measures once the probe is submerged, including low level and low velocity.
Velocity-area · no head loss
Uses the velocity-area method, No head loss, no standard flume.
No moving parts · no wrap or jam
No mechanical moving parts, No silt blockage or weed/debris wrapping and similar issues.
Class 10 corrosion resistance · intrinsic safety
High protection design, Class 10 corrosion resistance, explosion-proof (intrinsic safety), reliable in harsh duty.
Full / partial pipe
Open channel / river / drainage networkWorks in full and partial pipe Broad fit.
Three measurements · velocity / level / temperature
One probe takes three base quantities; an embedded model computes flow. Ranges, resolution, and accuracy below; ranges can be customized.
Velocity
Range 0.021–6.00 m/s, resolution 0.01 m/s, accuracy ≤1.0% ±1cm/s.
Water level
Range 0.03–10 m (customizable), resolution 0.001 m, accuracy 0.25% FS, repeatability <0.01 cm, hysteresis ≤0.2 cm.
Water temperature
Range −10–80 °C, resolution 0.1 °C, accuracy ±0.5 ℃, used for speed-of-sound compensation.
Open channel and pipe, one instrument
From rivers and open channels to pipes and drainage networks, full or partial pipe — no flume, measure when submerged, online or portable.
Velocity and level together,
flow comes out directly
Measure as soon as the probe is submerged. Zero dead band, no head loss. An embedded model turns velocity and level into instantaneous and totalized flow, uploaded live over Modbus RS-485, including reverse flow.
- TogetherVelocity + depth + temperature · one probe
- Direct outEmbedded model · instantaneous + totalized flow
- BidirectionalForward / reverse velocity · temperature-compensated speed of sound
- CommsModbus RS-485 · continuous online
Instrument specifications
General specifications for the HKI 306. Use them in a bid table; range and outputs can be customized. Contract documents govern the final configuration.
Which flow do you need to measure?
Specify an ultrasonic flow meter
Tell us the channel or pipe section, velocity and level range, and the install site. We will return a probe and range list — items can be adjusted.