Methods of manufacturing a fluid flow measuring device are provided. In an embodiment of the present invention, shields are disposed to prevent or reduce circulating electrical currents from causing a voltage difference that would adversely affect the measured voltage difference between two adjacent electrodes. Groups of sensors, e.g., two or more, may be placed within the shield. The shields may have any cross-section shape. A magnetic field source is disposed proximate the electrodes such that the magnetic field source is oriented to generate a magnetic field substantially orthogonal to an imaginary line intersecting each pair of electrodes. A voltage measuring circuit is electrically coupled to the plurality of electrodes and configured to measure a voltage difference between each pair of electrodes.