VEGA VEGASON 51K…53K - Manual (Page 34)

34 VEGASON 51K … 53K
Wrong
Mounting on a vessel with parabolic tank top
Correct
~ 1 /
2
vessel
radius
Wrong
Max. meas.
distance
Distance of the
transducer to the
vessel wall
Curve 1 (liquids)
Curve 2 (solids)
Mounting and installation
Sensor too close to the vessel wall
if the sensor is mounted too close to the ves-
sel wall (dimension A in diagram) strong false
echoes can be caused. Build-up, rivets,
screws and weld joints superimpose their
echoes on the product echo or useful echo.
Please ensure the sufficient distance of the
sensor to the vessel wall depending on the
maximum measuring distance (dimension B
in diagram). In case of good reflection condi-
tions (liquids, no vessel installation) we rec-
ommend the provision of the sensor distance
according to
diagram curve 1 . At a max.
meas. distance of, for example 10 m the
distance of the transducer, according to
curve 1, should be approx. 1 m. In case of
solids with bad reflection conditions provide
a distance to the vessel wall according to
diagram curve 2 . With very bad meas. con-
ditions it could be necessary to increase the
distance to the vessel wall or to gate out the
false echoes additionally by a false echo
storage and thereby adapt the sensor more
precisely to the environment.
Parabolic effects on dished boiler head
or basket arch vessels
Round or parabolic tank tops act like a para-
bolic mirror for the signals. If the sensor is
placed to the focus of such a parabolic tank
top the sensor receives amplified false ech-
oes. The optimum mounting is generally in the
range of half the vessel radius from the cen-
tre.
>
60 mm