Principles Of Operation - Loma IQ2 Service Manual

PRINCIPLES OF OPERATION

Inside the metal detector an electromagnetic field is used, operating at a similar
frequency to that used in AM broadcasting, through which the product passes.
This field interacts with both the product and any metal contamination within it, in
such a way that the interaction is measured to determine whether or not the
product is contaminated.
Figure 1 Metal detector with rectangular aperture and belt conveyor
A typical detector is shown in Figure 1. It consists of a metal box with an
aperture through which the product passes, and a control unit that processes
the signals. Inside the metal box, referred to as the search head, there are
three coils surrounding the aperture arranged as in Figure 2.
(transmitter) coil is driven by a powerful oscillator to generate a strong magnetic
field within the aperture, through which the product passes.
Module 7026
Configuration and Set up Information
Search head
A central
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