Patent ID: 8857268

Claim:
An electromagnetic flowmeter for measuring the flow of a medium through a measuring tube to provide corrosion protection of the electromagnetic flowmeter, comprising: first and second metallic measuring electrodes arranged on opposite sides of the measuring tube and in contact with the medium, a rate of flow of the medium in the measuring tube being measurable by measuring output signals from the first and second measuring electrodes representing a potential difference between the measuring electrodes induced by the flow of the medium in the measuring tube in a presence of a magnetic field; and a current source for passing a constant direct current to each of the first and second metallic measuring electrodes, the constant direct current passed to each of the first and second metallic measuring electrode being established to lower an electrode potential of a respective measuring electrode with respect to the medium to a level below a threshold value to render the respective metallic measuring electrode immune to corrosion with respect to the medium.