Monitor flow through large open channels and partially filled pipes with the new Greyline AVMS 5.1 Multi-Sensor Area-Velocity Flowmeter. Designed for municipal stormwater, combined effluent, raw sewage and irrigation water, the flowmeter uses three submerged ultrasonic sensors to continuously measure velocity at different points in the channel and provide an average velocity reading for flow monitoring. One of the three sensors can also monitor the water level or a separate non-contacting ultrasonic level sensor can be used in the system. The AVMS 5.1 can be calibrated to channels of any shape. The sensors are resistant to fouling and corrosion. It measures forward and reverse flow, includes a backlit flow rate display, totalizer, three 4-20mA outputs and two control relays. A built-in data logger is optional.