The size of the effective range of the magnet (shown in green) depends on the magnet width (a). The magnet width (a) must be sufficiently large to achieve the required dwell time in the magnetic field for lifting. The length of the magnet must at least correspond to the width of the conveyor belt so that the conveyor current is completely covered.

Care must be taken to ensure that the ferrous parts to be discharged cannot get caught on the edge of the belt, the material guide or the conveyor belt construction. The discharge area should be generously recessed.

We recommend that the conveyor belt should be mounded up. This improves the iron discharge and prevents damage caused by long or bulky iron parts becoming trapped between the magnet and the conveyor.

The carry-over of flat and fibrous material (films, cords, belts) is higher with cross discharge than with longitudinal discharge.

As soon as long or bulky iron parts are contained in the conveyed goods or the transport speed of the conveyed goods exceeds 3 m/s, the magnet should be positioned lengthwise above the head pulley.

The magnet width (a) must not be smaller than the width of the conveyor belt. We recommend aligning the centre axis of the magnet body tangentially to the head pulley. The end of the magnet body must not lie in front of the separating apex of the discharge chute. The upper part of the discharge chute and the head pulley must be made of non-magnetic materials.

We generally construct all permanent magnetic separators with two-pole magnet systems. These are more complex to manufacture, but offer significant advantages in operation compared to single-pole magnets.

Single-pole magnet systems work in all directions. Surrounding structural parts can therefore be magnetised and attract ferrous parts from the surrounding area. These then accumulate all over the magnetic separator and can quickly damage the discharge belt and rotating parts. Single-pole permanent magnets often look like hedgehogs after a short period of operation.

Two-pole magnet systems only act downwards and have no relevant stray fields in other directions. Iron parts can only be correctly and reliably attracted and ejected with downward-facing magnet systems.