MECHANICAL FLOWMETERS General purpose instruments for flow measurements in rivers, estuaries, canals, or with plankton nets to determine water volume for each tow. Each flowmeter is made with a nickel-plated brass nose cone, clear polycarbonate body, and is properly balanced to maintain horizontal position when suspended from the towing line. The precision molded rotor is coupled directly to a six digit counter that registers each revolution and displays it on an odometer. After sampling, remove meter and record reading and time. Subtracting the first reading from the second gives you your average speed over the sampling time. Unlimited depth capacity. Includes 8-3/8" long flowmeter, 18" stainless steel tow line and stainless steel connecting axle pin. Choice of regular or low speed impellers.
ELECTRONIC FLOWMETER
Combines a programmable electronic display and specially designed flowmeter with electronic sensor and underwater cable that allows users to show flow rate data in real time. The battery operated waterproof unit displays current velocity in cm/sec., ft./sec., m/sec. or knots, total distance traveled or volume in cubic meters. Other features include an event timer and external start/stop switch. Available with regular or low-flow impeller. See below. (Uses three 9-volt transistor batteries, included.)
Standard Impeller--For use in oceans, rivers, open channels or with towed nets. Range: 10 cm/sec. - 790 cm/sec. 6-digit counter measures 999999 counts, approximately 14.5 nautical miles. 2-3/4" diameter.
Low Speed Impeller--Features a 6-1/2" wide two-blade gray impeller with more surface area to sense slower currents. Range from 2 cm/sec. to 100 cm/sec. Available with either a 6 digit counter that measures 999999 counts, equal to approximately 14.5 nautical miles or 7 digit counter that measures 9999999 counts, equal to approximately 145 nautical miles. Replacement low speed impeller converts standard flowmeter to low speed.
Extendible Wading Rod--Telescoping aluminum rod has three 3-ft. sections that extend to 8 ft. to measure currents from river banks, bridges or hard to reach areas. Connects directly to Flowmeter by the stainless steel axle pin.