OCF 4.0 Open Channel Flow Monitor
Non-Contacting Ultrasonic Sensor
  • Accurate and Verifiable
  • Built-in 50,000 point Data Logger
  • Windows Software
  • USB and RS232 Outputs
  • 4-20mA/0-5V Output
  • 16-digit Totalizer
  • 3 Programmable Control Relays
  • Password Protected
  • Simple 3-key Calibration

OCF 4.0 Open Channel Flow Monitor
Continuously monitor, display, totalize and data log flow through any flume or weir. The OCF 4.0 includes a non-contacting ultrasonic sensor that mounts just 8" (203.2 mm) above the flowing water. It is accurate (±0.25%) and reliable. There is no obstruction to flow and no fouling. Use the built-in Keypad/menu system to select your flume or weir from the Menu and to choose measurement units (gallons, liters etc.)

The Greyline OCF 4.0 includes built-in 50,000 point Data Logger and flow reporting system. Retrieve data logs with 'Greyline Logger' software – included free with each OCF-4.0. Connect the USB or RS232 output directly to the serial port on your PC or Laptop, or by dial-up connection through modems. Configure the analog output to 0-5V for reduced power consumption.

Use the isolated 4-20mA to transmit flow to remote chart recorders or displays, and the 3 control relays are programmable for level/flow alarm, and flow proportionate pulse (for samplers, chlorinators or remote totalizers). An Intrinsic Safety Barrier is optional for sensor and cable installation in hazardous rated locations. The separate, watertight electronics/display enclosure is mounted at a convenient location within 500 ft (150 m) of the Senor Unit.



AVFM-II Area-Velocity Flow Monitor
For Open Channels and Pipes, Measures Velocity + Level to Calculate Flow
  • No Flume or Weir required
  • 3 Isolated 4-20mA Outputs (Flow, Level and Velocity)
  • Totalizer and 2 Programmable Control Relays
  • Simple 3-key Calibration - Password Protected
  • Optional Intrinsically Safe Sensor
  • Optional built-in 50,000 point Data Logger and Software




AVFM-II Area-Velocity Flow Monitor
Submersible Ultrasonic Sensor measures Level & Velocity Monitor flow through open channels, partially full sewer pipes and surcharged pipes without a flume or weir. Ideal for stormwater, combined effluent, raw sewage, irrigation water and streams.

The AVFM-II uses a submerged ultrasonic sensor to continuously measure both Velocity and Level in the channel. The sensor is a completely sealed ultrasonic unit with no orifices or ports. It mounts inside a pipe or at the bottom of a rectangular, trapezoid or egg-shaped channel. Calibration is simple: enter the pipe diameter or channel width and the AVFM-II computes the flow volume and displays the flow rate.


Stingray Level-Velocity Logger
For Open Channels and Pipes, Measures Velocity + Level to Calculate Flow
  • Stingray Portable Level-Velocity Logger
  • for Area-Velocity Flow Surveys in Sewers, Steams and Open Channels
  • Ultrasonic - Measures Level and Velocity
  • No Flume or Weir required
  • Powered by standard Alkaline D-cell batteries
  • 130,000 point Data Logger
  • Powerful Windows software
  • RS232 output
  • LCD bar graph display
  • Watertight



Stingray is a compact, battery-powered logger with an ultrasonic sensor. It data logs level, velocity and water temperature readings for flow monitoring through open channels, partially full sewer pipes and surcharged pipes. Use it for flow surveys, I&I studies, stormwater, irrigation water and sewage.

Stingray uses a submerged ultrasonic sensor to continuously measure both Velocity and Level in the channel. The sensor is a completely sealed ultrasonic unit with no orifices or ports. It mounts inside the pipe or at the bottom of a rectangular channel. No special compounds, tools or hardware are required.
Software is included with each Stingray. Use this powerful program to view Stingray readings in real-time and to set the logging interval. Greyline LoggerLog File Display
Retrieve Stingray log files. Data can be viewed in graph or table format and exported to spreadsheet and database programs.
Stingray stores up to 130,000 data points including level, velocity and water temperature. Between readings it powers down to conserve battery life. With 4 standard Alkaline D-cell batteries Stingray will operate up to 4 years!