Digital Flowmeters Effluent Flow Meter

Product Description

Operating Principle:

The electromagnetic flow meter is an instrument for measuring the flow of conductive fluid usingFaraday's electromagnetic induction law, and consequently the fluid must be electrically conductive. 

As illustrated below a magnetic field with density B - perpendicular to the direction of flow - stretches across a fluid flowing within an electrically isolated pipe.

The magnetic flux will induce a voltage difference (E) that can be measured between two electrodes arranged perpendicular to the direction of flow and the magnetic field. The voltage is proportional to thevelocity (V) of the fluid.

Measurement:

Electromagnetic flow meters mayhave eitherDirect Current(DC) orAlternating Current (AC) excitation. When systems are AC excited, electrostatic and/or electromagnetic noise may influence themeasurements. A DC excited system however, is less sensitive to noise produced by electromagnetic induction, simply because the voltage induced over the electrodes will be a DC voltage. The drawbacksare measurement errors due toelectro-chemical polarization between the electrodes and the fluid.The Electromagnetic Flow Meters are excited by a 2.5 Hz square wave and thereby eliminate thedrawbacks of bothDC and AC systems.

A microprocessor receives and measures the amplitude of the pulse with a 16 - bit resolution, andconverts and displays the result on the display unit.

The flowsensor shouldbe selectedso the flowvelocity throughthe sensor will be between 0.5 to 5.0 m/s. Flowtech recommends that flow velocities in tubes are kept between 1 “ 3 m/s for reliable and safeoperation.