Ultrasonic Open Channel Flow Meter – Vetrix UOCF Series


  • There are no special requirements for the cross-sectional shape and size of the channel.
  • It can be installed and maintained without stopping water.
  • No flow resistance, no water-head loss.
  • When the cross-section of the channel is large, multi-channel speed measurement is used to achieve high-precision measurement.
  • It can measure the flow and velocity in the forward and reverse directions.
  • Large measuring range and high accuracy.
  • It can be used for the calibration equipment of slot-weir or other open channel flow meters.

Dpstar is one of Malaysia’s leading experts for reliable flow monitoring solutions. Dpstar has the best selection of quality products. We offer a wide range of quality Flow Meter. Since the 90s, we have built a reputation for outstanding customer service and unrivaled expertise within our industry.

An ultrasonic flow meter can be defined as, a meter that is used to measure liquid velocity with ultrasound to analyze the volume of liquid flow. The instrument produced by our company uses ultrasonic waves through the air, a non-contact method to measure. Compare with contact instruments, it has higher reliability and durability in the condition of sticky dirt, corrosive liquid.

The Principle Of Ultrasonic Open Channel Flowmeter

The basic principle of ultrasonic laser ranging of ultrasonic open channel flow meter is according to the ultrasonic sensor installed on the weir (slot) flow measurement equipment, the single-chip microcomputer in the open channel flow meter is designed to output a certain frequency electronic signal to encourage piezoelectric crystallization in the probe to send an ultrasonic data signal of a special frequency, and start a timer at the time of sending and just start to count the time. The ultrasonic data signal is spread according to the measured liquid substance and hits the standard pole. Among them, apart caused the first reflection echo, and a part spread in the water again. A part of the reflection spreads in the reverse direction and enters the probe, causing the probe chip to oscillate, causing the conversion of sound, mechanical kinetic energy, and electromagnetic energy to make the probe output the first electronic signal. When the ultrasonic wave spread again in the water reaches the water surface, because there is vapor (gas) above the water surface, it causes a second reflection echo in the vapor-liquid interface layer, and the reflected echo is scattered and reflected back to the piezoelectric crystal. The probe outputs another electronic signal. That is, the first reflected echo is caused on the reference surface (standard rod), and the second reflected echo is caused on the vapor-liquid interface layer. When the probe receives the reflected wave, it immediately terminates the timing. At this time, the timing is recorded. The device records the propagation time t of the ultrasonic wave from sending to receiving. And t, according to the formula H: ht/t0, (h is the height-width ratio of the top of the weir (trough)) is the aspect ratio of the open channel flowmeter probe to the liquid level H.

How Does An Ultrasonic Open Channel Flow Meter Work?

An ultrasonic open channel flow meter uses ultrasonic reflection to determine the distance from the face of the ultrasonic transducer to the surface of the water. The elapsed time between when the signal is transmitted and when it is received determines the water level. The ultrasonic transducer acts as both a pulse emitter and an echo receiver.

Note that the speed of sound varies with air temperature, so for accurate flow measurement, the transit time must be corrected for the speed of sound changes caused by air-temperature changes. Many ultrasonic transducers have temperature sensors built-in, but others may require a stand-alone temperature sensor.

It is also important that the temperature sensor / ultrasonic transducer not be dramatically hotter (cooler is not usually a problem) than the air temperature – a sensor sunshade may be necessary.


  • Urban water supply diversion canal
  • Sewage treatment inflow and discharge channels
  • Discharge channels for chemical liquid and wastewater of industrial and mining enterprises
  • Water conservancy projects and agricultural irrigation channels
  • Discharge gate flow measurement


The Installation Of Parshall Flume


Function Compact type Remote type
Range 0.1l/s- 99999.99 m³/h
Cumulative Flow Max: 4290000000.00 m³
Max range for level 1m, 2m, 3m
Accuracy for Level 0.50%
Resolution 3mm or 0.1%
Display English LED
Accuracy for flow Standard weir:1- 5%
(meet the requirements of national standard weir and channels)
Non-standard weir: 10- 30%
Analog output (Four-wire system) 4- 20mA/750Ωload
Delay output (optional)two groups :AC 220V/ 8A or DC 24V/ 5A
Power supply Standard:24VDC 100mA;optional: 220V AC+15% 50Hz
Power supply (optional)12VDC, battery, solar
Environment temperature LED:-20- +60 C,Probe: -20- +80 C
Environment pressure Standard atmospheric pressure
Environment humidity ≤90%RH,Non-condensing
Process temperature -20- +80 C
Process pressure Standard atmospheric pressure
Communication Optional:485, 232, MODBUS protocol
Protection Grade LED:IP67 Probe: IP68 LED:IP65, probe:IP68
Cable Probe No Standard: 10m,
The longest: 100m
Probe installation dimension M48x2mm thread + matching nuts
Probe Material Standard: ABS
Teflon material in corrosive environment

Ordering Information

OUF 1 2 3 4 5 6 Description
Structure S Compact type
L Remote type (5m cable)
Channel Type TR Triangular Weir
RE Rectangular Weir
PA Parshall flume
Level Range 1 1m
2 2m
3 3m
Power Supply DC 24V DC
AC 220V AC
Communication 4 RS485
2 RS232
Probe Material AB ABS


Vetrix UOCF Series Ultrasonic Open Channel Flow Meter_DpstarGroup