Electromagnetic flow meter, has control- and evaluating unit determining flow based on determined parameter for compensating effects of variations of ohmic and/or capacitive coupling between coil arrangement and evaluating unit

摘要

The meter has a coil arrangement with coils (3, 4) for producing a magnetic field perpendicular to a flow direction of a medium flowing through a measuring pipe (2). A control- and evaluating unit (20) controls the coil arrangement and determines a flow depending on a voltage detected at an electrode arrangement. The unit determines a parameter i.e. voltage difference at electrode arrangement, for an ohmic and/or capacitive coupling between the coil arrangement and the unit. The unit determines the flow based on the determined parameter for compensating effects of variations of the coupling. An independent claim is also included for a method for operating an electromagnetic flow meter.