A rapidly rotating magnetic pole system induces eddy currents at high frequency in the highly conductive non-ferrous metal parts. These in turn generate magnetic fields of the same polarity as the magnetic rotor, which leads to the formation of the repulsive"Lorentz force" FL. This force acts against the force of gravity FG. In combination with the inertial force FT, acceleration out of the material flow is achieved.

In addition to the specific material properties, the throw distance is determined in particular by the size and shape of the part. Large parts are ejected further than small ones. Flat parts experience a higher induction per unit volume than thicker parts. Only very small eddy currents form in wire-shaped parts.

The strength of the induced currents and thus the repulsive forces depends on the specific electrical conductivity of the metal. The force of gravity is determined by the specific weight. The quotient of these two values is therefore a measure of the specific separability.

Aluminium, magnesium, copper, aluminium alloys and silver can be separated particularly well. The size ratio is less favourable for zinc, brass and tin. V2A, V4A and many high-alloy steels cannot be separated.

Any material part that lies above the separable non-ferrous metals makes ejection from the material flow more difficult or prevents it. A single-grain layer is therefore a basic requirement for optimum sorting and minimised carryover of good material.

We therefore recommend feeding the material to the eddy current separator across the entire working width using a vibrating conveyor trough.