Eddy Current Testing Technology - Bobbin Probes

In its most basic form - the single-element Eddy Current Testing (ECT) probe - a copper wire is excited with an alternating electrical current. This wire produces a magnetic field around itself in the direction ascertained by the right-hand rule. This magnetic field oscillates at the same frequency as the current running through the coil.
When the coil approaches a conductive material, currents opposed to the ones in the coil are induced in the material - eddy currents.
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