Multi parameter conductivity meter for measuring conductivity in water and wastewater

USI – Area Velocity Flow Meter

The Universal Smart Instrument (USI) is an innovative area velocity monitoring instrument and data logger that delivers multi-parameter measurements including area velocity flow and water quality in a single device.

The Universal Smart Instrument (USI) is an innovative Area Velocity monitoring instrument and data logger that delivers multi-parameter measurements including Area Velocity flow and water quality in a single device. Several standard instruments can therefore, be replaced by a single USI in a wide range of clean water and wastewater applications. Standard unit comprises 1xultrasonic sensor for area velocity flow measurement, 3 non-isolated4-20mA inputs and 2 isolated 4-20mA outputs, 1 dedicated pH input, Ethernet and RS422 or Modbus communications. 6 programmable relays. The USI can input variables from other 4-20mA devices or from up to 4 Modbus sensors for control and measurement. For full details of the USI’s range of measurement and control refer to the product brochure.


  • Advanced Area Velocity Flow meter with integral pH/ISE meter
  • Optional Turbidity, Dissolved Oxygen, Temperature and Conductivity inputs
  • Optional measurement ofAmmonia, Ammonium, Chloride, Calcium, Fluoride, Nitrate, Potassium.
  • Quick and simple user-friendly programming
  • Integral 30-year data logger
  • PC based reporting software
  • IP 66/4X Wall mounted weatherproof enclosure
  • 6 Programmable relays
  • 4-20mA inputs and outputs


  • Sewer Flow monitoring and data logging
  • Irrigation Channels
  • Waste Water Monitoring
  • Storm Water
  • Open Channel Water Monitoring
  • Flow Surveys
  • Combined Flow and Water Quality measurement

Instruction Manual

The USI Area Velocity meter comes with a sensor for insertion into a pipe or channel.

Choose the length of sensor cable so that the display can be located outside the pipe or channel.

The sensor must be fixed into the pipe or enclosure using either a fixed bracket which is screwed into the pipe or channel wall or the adjustable plastic spring band which allows the insertion into a pipe without permanent fixing.

Isolated 4-20mA inputs are required where the input cable may be subject to high voltage spikes either from other electrical machinery or lightening. These could seriously damage the USI and in such applications isolated inputs should be added as an option.

The USI AV flow meter also allows the measurement of other water quality parameters at the same time and has the same functionality as the USI flow. See USI Flow Meter Buyers guide.

To implement the pH meter, purchase an ISE pH sensor which will connect direct.

You can add further Modbus water quality sensors from a choice of:

pH, Turbidity, Dissolved Oxygen and conductivity. Each of these sensors has an integral temperature sensor.

One Modbus sensor can be connected directly to the USI. However up to four Modbus sensors can be connected via the optional interface box.

The USI will log all parameters measured for up to 22 years. It comes with a pc based software package and a USB stick as standard. Data can be downloaded onto

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