The measuring principle of electromagnetic
flowmeter is based on the electromagnetic
induction law of Farady. The sensor is mainly
composed of measuring tube with isolate lining, a
pair of electrodes installed by penetration of the
measuring tube wall, a pair of coils and iron core to
produce working magnetic field. When the
conductive fluid flows through the measuring tube
of the sensor, the voltage signal in direct proportion
to the average flow velocity of the fluid will be
inducted on the electrodes. The signal is amplified
and treated by the transmitter to realize various
display functions.