Flow & Current Meters

AA & Pygmy Current Meter

The AA Current Meter has proven itself to be a versatile instrument with a long history of accuracy, reliability, and durability. The precisely balanced bucket wheel is mounted on a vertical pivot and is rotated by water flow. The rate of rotation is proportional to water velocity, streamflow velocities from 0.1 to 25 feet per second (0.03 to 7.6 meters per second) can be measured. The main features of this meter are the uniquely designed bucket wheel shaft bearings and the two post contact chamber. The bucket wheel has six conical shaped cups, is five inches (12.7 cm) in diameter and rotates on a vertical axis inside the yoke. The AA current meter may be suspended by means of a wading rod while wading a stream or by cable from an overhead structure. A tailpiece assembly assures proper alignment of the meter to water flow when suspended by a cable. Velocity is determined by counting the number of revolutions of the bucket wheel over a given period of time. Revolutions can be monitored by several means. A headset can be used to manually count the revolutions via an audible tone produced every revolution. Number of revolutions over a period of time are then compared to a rating chart (provided with each meter) which determines water velocity. Separate binding posts on the contact chamber allow the operator to selectively count either every revolution or fifth revolution for use in fast moving water. Also available is the Pygmy Current Meter for shallow, slow wading survey applications. Specifications and Accessories.