Mainstream IV Portable


Mainstream uses the area-velocity method to give a continuous or time sampled measurement of fluid flow. Suitable for any liquid containing bubbles or suspended solids, even in minute quantities, the velocity probe detects reflected ultrasound.


Signals from the probe are analysed using Phase Coherence Processing (patents pending). Phase Coherence Processing only accepts signals containing verified velocity information. The percentage of signal accepted is the signal quality.

A high signal quality confirms the integrity of the measurement. The verified velocity signals produce a histogram of the flow velocities. Analysing this histogram gives the mean flow velocity.

The liquid level is measured by a submerged pressure transmitter or ultrasonic sensor.

Flow cross-sectional area is deduced from the liquid level measurement and a stored description of the pipe or channel cross-section.

The flow velocity is multiplied by the flow cross-sectional area to give the flow rate and integrated to give the total discharge.


  • Effluent Monitoring
  • Waste Water Treatment
  • Industrial Flow Measurement
  • Irrigation Channels
  • River/Stream Flow Measurement
  • Water Distribution

Features and Benefits

  • Quick to install - no weirs or flumes.
  • Bi-directional flow measurement for forward and reverse velocities from 10 mm/s up to 5 m/s
  • Streamlined velocity probe eliminates fouling and reduces flow disturbances.
  • High sensitivity extends applications to 'clean' water.
  • Powerful, easy to use PC software simplifies flow meter commissioning.
  • Sophisticated ultrasound processing ignores spurious signals.
  • Ultrasound signal quality monitor confirms measurement integrity.
  • High capacity data logger for long term records of level, velocity and flow rate.
  • Opto-isolated switch outputs for alarms and controls.
  • Optional modem for dial-up access and internet connectivity.

System Unit

Case body

Ultra-high impact structural copolymer polypropylene.


The case meets MIL-STD 4150-H.


270 mm wide x 250 mm deep x 180 mm high

5 kg
Operating temperature range
10° C to 70° C