Electromagnetic flowmeters


  • Low pressure drop
  • No moving parts means less wear, no routine maintenance
  • Insensitive to density, viscosity, pressure, temperature and flow profile
  • Usable for a variety of otherwise difficult to meter fluids
  • Accurate (error range of 0.5%)
  • Relatively low cost
  • Measures independently of temperature, pressure, density, viscosity, and electrical conductivity
  • Measures forward and reverse flow
  • Can be used with pipes of varying sizes


  • Can only meter liquids
  • Liquids must be conductive
  • Nearby electromagnetic noise causes interference
  • Will not work in partially full pipes, even if electrodes are wetted
  • Requires lengths of straight pipe upstream and downstream
  • Allowing sludges and greasy fluids to flow too slow causes buildup, which affects measurement