Eddy Current Probes

Eddy current probe systems are made up of a coil, embedded in the tip of the probe, a separate driver unit and an interconnecting ‘tuned’ length of cable. The principle of operation, as the name implies, depends upon the eddy currents set up in the surface of the target material.The coil is supplied with a constant r.f current from the remote eddy probe driver, which sets up an electro-magnetic field between the tip and the observed surface.

Any electrically conductive material within this electromagnetic field, ie. the target material, will have eddy currents induced in it’s surface. The energy absorbed from the electromagnetic field to produce these eddy currents will vary the strength of the field, and hence the energising current, in proportion th the probe target istance. such changes are sensed in the driver where they are converted to a varying voltage signal. The whole probe, extension cable and driver system relies for it’s operation on being a tuned circuit and as such is dependant on the system’s natural frequency. Thus each system is set up for a fixed electrical/cable length. Eddy probe systems are usually supplied with 2,5,9 or 14 metre total cable lengths.

SENTURION eddy current probes have been designed to be the most robust available and are ideally suited to a vast range of industrial applications.