This machine works thanks to electromagnetism.
The detector produces an altern current which goes through a coil and creates and electromagnetic field. When a piece of metal goes under the metal detector head, the electromagnetic field is modified and a signal is sent to the detector., which makes the alarm work.
The higher is the tunnel the lower is it´s sensitivity
Regarding the recycling sector, the detector is detachable. Moreover, it has a mooring system for the detector to be fastened. To be installed, the detachable part should be open for the conveyor belt to go through the head tunnel and be closed afterwards.
Its tightness coefficient is IP67, which means the detector is able to work under extrem enviromental atmospheres. Related to this point, the control panel tightness coefficient is IP65, this way it can also be installed out in the open.
Food companies also need meetal detectors. At this point, the detectors are independent machines due to they have got their own conveyor belt. This way, the metal detector can be, either integrated within a manufacturing process, or work on its own and beeing feeded by a worker.