New

Velocity transmitter - ultrasonic sensor, 4–20 mA output | MAINSTREAM MEASUREMENTS

Ultrasonic velocity transmitter with 4–20 mA output for water monitoring in open channels, sewers and part-filled pipes.

Request a quote

PRICE ON REQUEST

The Velocity Transmitter is a high-performance velocity measurement transmitter designed for use as a system component in open channel and part-filled pipe applications. It uses an immersed ultrasonic velocity probe to measure flow velocity with high sensitivity and strong signal validation. The unit is intended for installations requiring reliable velocity data, simple integration, and PC-based configuration and diagnostics.

Advantages

Dedicated velocity measurement transmitter for open channel and part-filled pipe systems
Ultrasonic velocity measurement from 10 mm/s up to 5 m/s
High sensitivity suitable for relatively clean water applications
Streamlined velocity probe that limits fouling and reduces flow disturbance
Real-time signal processing to reduce power consumption
Smart power saving mode that adapts acquisition time to flow and signal quality conditions
Ultrasound signal quality monitoring to confirm measurement integrity
One configurable 4–20 mA output for integration into monitoring and control systems
Up to 500 m distance between system unit and velocity sensor
PC software support for commissioning, diagnostics, display, and export

Main Features

Measurement principle	submerged ultrasonic velocity measurement
Method	phase coherence time delay measurement
Velocity range	from -5 m/s to -10 mm/s and from 10 mm/s to 5 m/s
Resolution	better than 1 mm/s
Measurement integrity	ultrasound signal quality monitor indicating the proportion of useful velocity information
Derived output	velocity, power supply, and quality signal via 4–20 mA output configuration
Power supply	external 12 V and 24 V supplies
Power monitoring	supply voltages viewable through the user interface
Local communications	RS232 and USB compatible interface with automatic baud rate detection
Remote communications	optional external SDI or GPRS device
Software	Mainstream Communicator UI software for configuration, diagnostics, real-time measurement display, and data retrieval
Velocity units	mm/s, cm/s, m/s, in/s, ft/s, ft/min
Analog output	one configurable 4–20 mA output
Velocity sensor protection	IP68
Minimum operating depth	30 mm
System enclosure	IP67 with electronics encapsulated to IP68
System unit dimensions	220 x 120 x 80 mm
System unit weight	1.5 kg

Typical applications

Effluent monitoring
Waste water treatment
Industrial flow measurement
Irrigation channels and canals
River and stream flow measurement
Water distribution
Sewer flow measurement including inflow and infiltration and CSO monitoring
Portable and fixed-site flow measurement with weirs and flumes

Why choose Velocity Transmitter

The Velocity Transmitter is a strong choice for users who need reliable ultrasonic velocity measurement in water and wastewater systems without the added complexity of a full flowmeter configuration. Its combination of measurement integrity monitoring, compact industrial hardware, 4–20 mA integration, and PC-based commissioning tools makes it well suited for applications where stable velocity data and straightforward system integration are essential.

What should you check before choosing this product?

Check the pipe or channel geometry, flow conditions and sensor installation requirements. Confirm the measurement range, output interfaces and power supply for the intended monitoring point.