Magnetic flowmeters are used with conductive liquids of minimum conductivity 5µs/cm.
Measurement is based on electromagnetic induction. Electromagnets create a magnetic field while the conductive medium flows through the magnetic field, giving rise to potential. As the flow rate rises, the voltage increases according to the following formula:
- U = B*I*V
- U = induced voltage
- B = magnetic flux density
- I = distance of measuring electrodes
- V = medium flow velocity
Wide measuring range as an advantage
In addition to the wide measuring range, magnetic meters constitute a relatively cheap measurement method for liquids.
The measuring tube is typically lined with rubber or Teflon, but for abrasive applications, it is also available without lining.