Eddy current testing is one of several non-destructive testing methods that use the electromagnetism principle. Conventional eddy current testing utilises electromagnetic induction to detect discontinuities in conductive materials. A specially designed coil energised with alternating current is placed in proximity to the test surface generating changing magnetic-field which interacts with the test-part producing eddy current in the vicinity.Variations in the changing phases and magnitude of these eddy currents is then monitored. The electrical conductivity variations or magnetic permeability of the test-part, or the presence of any discontinuities, will cause a change. The changes are shown on a screen for easy interpretation.