MICRO-EPSILON eddyNCDT SGS 4701, Руководство по эксплуатации

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System Description
eddyNCDT SGS 4701
2. System Description
2.1 Measuring Principle
The eddyNCDT series SGS 4701 (Non-Contacting Displacement Transducers) measuring system operates on
the basis of eddy currents without making physical contact. It is used for measurements on objects consisting
of electrically conducting materials which have ferromagnetic or non-ferromagnetic properties.
High frequency alternating currents flow through a coil cast in a sensor housing. The electromagnetic field
from the coil induces eddy currents in the electrically conducting target, causing the alternating current
resistance of the coil to change. This change of impedance delivers an electrical signal proportional to the
distance of the target from the sensor.
The eddyNCDT SGS 4701 conditions the sensor signals user-fairly at a bandwidth of 2,000 Hz. Thus a
so-called spindle monitoring is also still possible at numbers of revolutions up to 120,000 rpm. The spindle
growth itself can be detected at even higher numbers of revolutions.
Monitoring an axial expansion requires subsequent individual filtering by the user. Micro-Epsilon recommends
averaging or filtering across several revolutions in order to record only the relative expansion during a defined
period. During an unfiltered/non-averaged measurement, effects such as those within a single revolution also
become visible; this can cause incorrect interpretations.
In order to achieve highly accurate measurements, it is imperatively necessary that one (or more) sample(s)
item under test is / are provided by the customer.