Developed as a non-contact alternative to the limit switch
(limit switches require physical contact, they are prone to failure
through wear, fatigue and accidental jamming)
Principle An inductive detector senses the proximity of
a metal object using an oscillator principle Surface currents,
known as eddy
currents, are induced in the metal target, and they react with
the oscillators field
the closer the proximity, the stronger the reaction
When the metal target is outside of the oscillator field, the
magnitude of the oscillations is not impeded.
When the target is inside the field, it attenuates the magnitude
of the oscillations, eventually stopping the oscillator.
The threshold level detector (trigger circuit) shapes the output
signal of the sensor into a clear-cut ON-OFF (here/not here) type
of signal.
ON point (operating level) is a different level than the OFF
point (releasing level). The difference between these points is
called differential or hysteresis.
SENSING DISTANCE
Factors affected for the performance of Inductive sensors
