VEGAVIB and VEGAWAVE are point level sensors based on the vibration
principle. VEGAVIB is equipped with a vibrating rod as sensor
element,
VEGAWAVE has a tuning fork.
Both are designed for industrial use in all areas of process
technology and are deployed mainly in bulk solids.
The vibrating element (vibrating rod or tuning fork) is energized
piezoelectrically and vibrates at its mechanical resonance
frequency. The piezos are mechanically fixed and hence not subject
to temperature shock limitations. When the vibrating element is
immersed in the product, the vibration frequency changes. This
change is detected by the integrated electronics module and
converted into a switching command.
Typical applications are overfill and dry run protection systems.
Due to the rugged vibration measuring system, the vibrating level
switches remain virtually unaffected by chemical and physical
properties of the bulk solid.
They also work when subjected to strong external vibrations or
changing products.
Function monitoring
The electronics module continuously monitors the following
criteria:
•Correct vibrating frequency
•Line break to the piezo drive
If one of the stated malfunctions is detected or in case of voltage
supply,
the electronics takes on a defined switching status, i.e. the relay
deener
gises (safe state).
Solid detection in water
With instruments in the version for solid detection in water
(option), the vibrating element is adjusted to the density of
water. If submerged in water (density 1 g/cm³), the level switch
signals "uncovered". Only if the vibrating element is also covered
with solids (e.g. sand, sludge, etc.) will the sensor signal
"covered".
