Contrec 515-OC01

Open Channel Flow Computer for Frequency Flow Meter and Analog Level Sensors

The OC01 application measures the flow of fluid in an open channel by using a frequency flowmeter with a velocity proportional output and an analogue level input. The level input in conjunction with entered dimensional parameters is used to determine the cross-sectional area of the fluid in the channel.

Several regular channels are catered for including: Rectangular, Triangular, Trapezoidal, Circular and Half-Round. Flow can be measured in other channel shapes with a Non-linear selection that allows the level input to represent the actual cross-sectional area of the fluid at various levels.

Calculations

The volume calculation is based on the multiplication of the cross-sectional area and the velocity of the fluid in the channel.

Volume flow = velocity x area

The area for one of the selectable channel shapes is derived from the channel dimensions (width, base or diameter) and the input from the level sensor. For “non-linear” channels, parameters are available to allow the area to be read directly from the level input via a series of correction points.