Procedure for operating an electromagnetic flowmeter designed to measure the flow velocity or the volume flow of a medium in a measuring tube, said electromagnetic flowmeter comprising: a measuring tube to conduct the medium; a magnet system with at least a coil system (21, 22) designed to generate a magnetic field in the medium, wherein the magnetic field is essentially perpendicular to a measuring tube axis, wherein the magnetic field is produced by the application of an electrical coil voltage to the coil system (21, 22); at least a pair of measuring electrodes, arranged in the measuring tube, designed to measure an electrode voltage, induced by the magnetic field, in the medium, said electrode voltage being essentially proportional to the flow velocity and the intensity of the magnetic field; a measurement/operation circuit designed to operate the magnet system and evaluate the electrode voltage, wherein the magnetic field is generated during a feed phase and the electrode voltage is measured, wherein the feed phase has a measurement phase in which the magnetic field is essentially constant, wherein a value of the electrode voltage measured during the measurement phase is used to calculate the flow of the medium wherein a final state is a state of a stabilized measuring system, said final state being used to calculate the flow of medium, wherein a magnetic field of inverse polarity is generated during a subsequent feed phase, characterized in that the switch between feed phases causes an electrical voltage pulse to be produced in the medium; wherein the voltage pulse is analyzed to obtain information on the course of a deviation of the electrode voltage in relation to the final state, wherein a measured value of a first impedance of an electrical circuit comprising the measuring electrodes and the medium or a second impedance of the medium is determined, wherein the measured value of the first impedance or the measured value of the second impedance is used to analyze the voltage pulse, wherein the course of the electrode voltage is corrected depending on the course of the deviation. a measuring tube to conduct the medium; a magnet system with at least a coil system (21, 22) designed to generate a magnetic field in the medium, wherein the magnetic field is essentially perpendicular to a measuring tube axis, wherein the magnetic field is produced by the application of an electrical coil voltage to the coil system (21, 22); at least a pair of measuring electrodes, arranged in the measuring tube, designed to measure an electrode voltage, induced by the magnetic field, in the medium, said electrode voltage being essentially proportional to the flow velocity and the intensity of the magnetic field; a measurement/operation circuit designed to operate the magnet system and evaluate the electrode voltage, wherein the magnetic field is generated during a feed phase and the electrode voltage is measured, wherein the feed phase has a measurement phase in which the magnetic field is essentially constant, wherein a value of the electrode voltage measured during the measurement phase is used to calculate the flow of the medium wherein a final state is a state of a stabilized measuring system, said final state being used to calculate the flow of medium, wherein a magnetic field of inverse polarity is generated during a subsequent feed phase, characterized in that the switch between feed phases causes an electrical voltage pulse to be produced in the medium; wherein the voltage pulse is analyzed to obtain information on the course of a deviation of the electrode voltage in relation to the final state, wherein a measured value of a first impedance of an electrical circuit comprising the measuring electrodes and the medium or a second impedance of the medium is determined, wherein the measured value of the first impedance or the measured value of the second impedance is used to analyze the voltage pulse, wherein the course of the electrode voltage is corrected depending on the course of the deviation.