Current Meters and Open Channel Meters have been a speciality of Valeport's since the company was first formed in 1969. The company started making instruments for measuring the speed of the water in London's River Thames, since then our product range has grown, but our expertise in current flow measurement remains.
Whichever type of instrument your require, whether it's the traditional impeller mechanism, or the high accuracy electromagnetic type, Valeport can offer a solution. Configurations are available that are suitable for use in a wide variety of applications, from hand held measurements in the smallest streams, through modelling experiments in the laboratory, to self-contained instruments for navigable rivers, estuaries, ROVs and the deep ocean.
Our impeller instruments use the simple premise of measuring the speed of rotation of a helix in the water. PTFE bearings eliminate the need for specialised lubricants and the magnetic contact closure minimises the moving parts in the system - this also allows the sensor itself to be remote from the measuring electronics (ideal in deep water applications).
The electromagnetic sensors use the Faraday Principle to measure the water speed. As a conductor (water) moves through an electromagnetic field (generated by the sensor), it generates a voltage that is measured by the sensor electrodes. Modern day signal conditioning electronics and filtering techniques allow highly accurate measurements to be made, and there is a choice of sensor shapes and sizes to suit the application. The solid state sensors and standard titanium / polyurethane construction provide excellent corrosion resistance, and depth ratings up to 5000m.