Doppler flow technology - the next generation is here, performing and re-writing the rule-book!

Doppler flow technology - the next generation is here, performing and re-writing the rule-book!

Keywords: Flowmeters, Measurement

Overcoming many of the limitations of previous types of Doppler flowmeters,Onix Measurement's latest family of non-invasive, clamp-on flowmeters, the Hydra SX dual frequency Doppler range, is now performing in a broader spectrum of applications: even for the measurement of cleaner liquids, end users can be sure of selecting the right technology for their applications (see Plate 2).

Dual frequency Doppler (DFD) (patent pending) technology was developed by Onix Measurement's sister company, Polysonics Inc., a market leader in the development, manufacture and supply of ultrasonic, non-invasive flowmeters into the worldwide market. The main drive behind the development of DFD was the desire to minimise the erratic effects of "site noise" on flow measurements -giving users a consistent, repeatable and inherently more reliable reading.

Plate 2 The Hydra SX dual frequency Doppler

Unlike conventional Doppler flowmeters, which operate on a single frequency,DFD generates two independent ultrasonic signals at different frequencies. The frequencies are used automatically to identify and eliminate noise errors. The operation of the instrument is then enhanced by an "expert system" which allows the flowmeter to automatically "learn" the application parameters - resulting in a simple four-step set-up routine that significantly reduces commissioning time.

The Hydra SX range gives superior performance in the real-time measurement of homogeneous liquids that contain gas bubbles or suspended particles. Traditional markets for the Polysonics Doppler flowmeters include primary and secondary sewage processing as well as industrial processing such as process monitoring and effluent treatment.

To address the differing requirements of the user, the DFD range includes the battery operated, portable SX30, housed in an IP67 carry case, and the dedicated SX40, housed in an IP65 flame retardant rugged housing.

For continuous flow recording, an integral, powerful 90,000 point data logger avoids the need for additional chart recorders or external data loggers. Up to four independent programmable relays can be selected for functions such as pump control, fault indication, limit switching, sampler activation, power down alarming or remote totaliser driving.

For more information contact: Sue Fielder, Publicity Manager, Onix Measurement Ltd, King's Worthy, Winchester, Hampshire SO23 7QA. Tel: +44 (0)1962 625000; Fax: +44 (0) 1962 885530; E-mail: flow_uk@compuserve.com