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Unformatted text preview: ss powerful effect on the various switching distances of different
materials with the typical oscillator frequencies used. As a rule, the oscillator
frequency for inductive proximity sensors is in the range of 300 – 800 kHz.
Up to now, the dependence of the switching distance of the material to be
attenuated could not be calculated explicitly. Power dissipation in the
attenuating material Losses are created as a result of eddy currents in a metal plate. Assuming that the
depth of penetration of the field is small and that the approaching field does not
penetrate the metal plate, the following applies:
f © Festo Didactic GmbH & Co. KG • FP 1110 = r.m.s value of the magnetic field strength of the stray field on the plate
= µ0 · µr = Magnetic permeability,
= 1.257 · 10-6 Vs/Am = Magnetic field constant,
= Relative permeability
= Electrical conductivity
= Frequency 161 11. Physical fundamentals The value of H0 depends on the distance of the plate from the proximity sensor and
from the field distribution. P...
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This note was uploaded on 11/01/2012 for the course CHEMICAL 102 taught by Professor Jamesrodriguez during the Spring '12 term at Universidad Politécnica de Cartagena.
- Spring '12