Reliable Weir Flow Starts With the Right Geometry Weir Ultrasonic Flow Meter is designed for triangular, rectangular, equal-width and other supported sharp-crested weir installations. Small errors in crest height, notch angle, upstream head or zero reference can create a large error in calculated flow, particularly at low rates. A non-contact ultrasonic sensor provides continuous head measurement while the controller applies the selected weir equation and totalizes volume. Flexible Algorithms for Common Weir Profiles The ultrasonic sensor measures liquid level without touching the medium. The controller converts that level into flow using the programmed equation for a Parshall flume, rectangular weir, equal-width weir or triangular weir, and displays both instantaneous flow and accumulated volume. Gallop lists automatic temperature compensation, adjustable interference shielding and multiple built-in channel algorithms. Standard product information also identifies 4-20 mA, RS485 and RS232 outputs, 24 VDC or 220 VAC supply options, and split waterproof or compact configurations. The arrangement suits wastewater, industrial discharge, irrigation and laboratory channels where a defined primary structure is already present. This page can naturally support buyer terms such as open channel flow measurement, ultrasonic level sensor, flow totalizer, flume flow meter and weir flow monitoring. Control Crest, Zero and Approach Conditions Confirm notch angle or crest width, maximum head, nappe ventilation, upstream ponding and the correct measurement distance from the crest; remove deposits that change the opening. Choose output scaling, low-flow cutoff, damping and alarm settings so the instrument reports meaningful data rather than amplifying surface ripple or splash. Accuracy depends on correct flume or weir construction, a stable upstream approach, the correct zero reference and a clear acoustic path; foam, heavy vapor, turbulence and submerged primary devices require engineering review. Gallop states a one-year warranty, long-life maintenance and installation guidance. Include commissioning support, spare-part recommendations and response expectations in the commercial review so service terms are as clear as the instrument specification.