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Working Hours

Mon - Fri: 08:00 - 16:00 (EET)
Sat: Closed
Sun: Closed


for difficult liquids, wastewater, slurries, sludge, chemicals, crude oil, etc

Model 5.v0

Model 5.v0 is ideal for "difficult liquids" that would damage regular flow meters - wastewater, slurries, sludge, chemicals, viscous liquids and abrasives. There is no obstruction to flow and no pressure drop. The standard, strap-on ultrasonic sensor fits any pipe 1/2" (12.5 mm) Inside Diameter or larger. The electronics/display enclosure can be mounted nearby.

Use the isolated 4-20mA to transmit flow to remote displays, recorders or controllers. The 2 programmable relays can be used for flow control, pump protection or flow proportionate pulse. Calibration is easy with the built-in 3-key calibrator. Display and totalize flow in your choice of engineering units (gallons, liters etc.)

Sensor cable can be extended up to 500 ft. (152 m) with no loss of signal. Model 5.v0 can be equipped with intrinsic safety barriers for sensor installation in hazardous rated locations. Other options include high temperature sensors and a built-in 2 million point Data Logger.
Model 5.v0 includes a new digital signal processor to filter background noise and interference and to measure flow rates between 0.2 to 40 ft/sec (0.06 to 12.2 m/sec) with accuracy of ±2% of full scale on liquids with entrained particles or gases of 100 microns or larger and minimum concentrations of 75 ppm. The flow meter operates with a single-head flow sensor mounted externally on any contiguous pipe material that conducts sound including: carbon steel, stainless steel, ductile iron, copper, FRP, PVC, ABS, or cement lined pipe from 1/2" to 180" (12.5 mm to 4.5 m) ID.

Main Features

Non-Contacting Ultrasonic Sensor
Display: Large, White, backlit matrix - displays flow rate, relay states, 16-digit totalizer, operating mode and calibration menu
16-Digit Totalizer
power input - 100-130VAC 50/60Hz
Isolated 4-20mA (1000 ohm)
2 control relays, rated 5 amp SPDT, programmable flow alarm and/or proportional pulse
proportional pulse output, and/or flow alarm
Automatic Sensitivity Adjustment
Intrinsically Safe Sensor Option
Built-in 5-Key Calibrator
sensor - strap-on, single head ultrasonic for 1/2" to 180" (12.5 mm to 4.5 m) ID pipes
sensor operational temperature: from -40°C to 150°C (-40°F to 300°F)
sensor cable - 20ft / 6m shielded coaxial pair
accuracy of ±2% of full scale on liquids with entrained particles or gases of 100 microns or larger and minimum concentrations of 75 ppm
Repeatability: ±0.1%,
Linearity ±0.5% of full scale
enclosure - watertight NEMA4X (IP66) polycarbonate

How it works

Model 5 Ultrasonic Doppler flow meters measure flow from outside a pipe with a strap-on sensor. Model 5 meters continuously transmit high frequency sound (640 kHz) that travels through the pipe wall and into the flowing liquid. Sound is reflected back to the sensor from solids or bubbles in the fluid. If the fluid is in motion, the echoes return at an altered frequency proportionate to flow velocity. Model 5 flow meters continuously measure this frequency shift to calculate flow.

The Doppler technique only works on liquids which contain solids or gas bubbles to reflect its signal. These are "difficult" liquids that may damage regular flow meters: slurries, sludge, wastewater, abrasives, viscous and corrosive chemicals. Because the sensor mounts on the outside of the pipe, there is no pressure drop and no obstruction to flow.

For best performance Doppler sensors should be mounted away from turbulence creating devices like pipe elbows and tees, and away from velocity increasing devices like controlling valves and pumps. Typical accuracy is ±2% of full scale.


Built-in 2 million point logger with USB output and Windows™ software
Sensor Cable 15m Extension Cable
Power Input 9-32VDC