Thermo Scientific Oretronic III, Operating & Service Manual

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Introduction
1-2 Introduction Thermo Fisher Scientific
REC-4105 Rev L
Figure 1–1. Magnetic Fields Generated by the TMD
The material on the conveyor belt also produces a secondary magnetic
field. The two magnetic fields can be distinguished from each other
by observing their decay times. The better the conductivity
characteristics of the material, the longer the decay time. As the
magnetic field decays, the output signal strength decreases (see Figure
1-2).
Figure 1–2. How Conductivity Affects Decay Time
RECEIVER
COIL
TRANSMITTER
COIL
PRIMARY
MAGNETIC
FIELD
TRAMP
METAL
SECONDARY
MAGNETIC
FIELD