Magnetic-inductive volumetric flowmeter using detection of voltage induced in flow medium by magnetic field in measuring pipe with control circuit for controlling potential of reference electrode

摘要

The flowmeter has a magnet providing a magnetic field within the measuring pipe (4) through which the flow medium is passed, having a magnetic field component perpendicular to the flow direction, the voltage induced in the flow medium detected via a pair of electrodes (2,3) connected to respective inputs of a pre-amplifier (5). A control circuit with an inverted difference amplifier circuit (6) is used for controlling the potential of a reference electrode (1) in galvanic contact with the flow medium, for adjusting the counter-clock input voltage and/or the potential range of the pre-amplifier control range. An independent claim for a measuring method for a magnetic-inductive volumetric flowmeter is also included.