Rugged flow meters (32997-series) from Cole-Parmer Instrument Co., of Vernon Hills, Ill., have no moving parts—ideal for wet tap or hot tap installations for general water applications. As fluid flows through the meters, vortices form and move downstream. The frequency of the vortices is directly proportional to the flow rate. These vortices cause pressure fluctuations, which are sensed, amplified and converted into an analog signal. Select a flowmeter for fixed insertion or with a retractable insertion.