Thermo Scientific Oretronic III, Operating & Service Manual

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Introduction
Thermo Fisher Scientific Introduction 1-3
REC-4105 Rev L
Coal, aggregate, and mineral ores have conductivity characteristics
considerably poorer than tramp metal, which means their magnetic field
decays more quickly (see Figure 1-3).
Figure 1–3. Ore/Tramp Metal Decay Time Comparison
The Oretronic III TMD is designed to take advantage of the difference in
decay time by activating its measurement window (the point at which it
reads the output signal) only after the magnetic field from the material
on the conveyor has decayed and before the tramp's decay has ended
(see Figure 1-4. Using this measurement window timing helps prevent
both false trips and passed tramp metal.
Figure 1–4. Measurement Window Timing