VEGA VEGASCAN 850 - Manual (Page 50)

50 VEGASCAN 850
If the sensor is mounted too close to the
vessel wall (dimension A in diagram), strong
false echoes can be caused. Buildup, rivets,
screws or weld joints on the vessel wall su-
perimpose their echoes onto the product or
useful echo. Please ensure a sufficient dis-
tance from the sensor to the vessel wall,
depending on the maximum measuring dis-
tance (dimension B in diagram).
In case of good reflection conditions (liquids,
no vessel installations), we recommend de-
termining the sensor distance according to
Diagram curve 1 . At a max. meas. distance
of e.g. 10 m, the distance of the transducer
(according to curve 1) should be approx.
1.5 m.
In case of solids with bad reflection proper-
ties, determine the distance to the vessel wall
according to
Diagram curve 2 . Under very
bad measuring conditions (rough vessel
walls, struts), it might be necessary to in-
crease the distance to the vessel wall, or to
additionally filter out the false echoes by
storing them in memory, thereby adapting the
sensor more precisely to the environment.
Mounting and installation
Strong heat fluctuations
Strong heat fluctuations, e.g. due to the sun,
cause measuring errors. Please provide a
sun shield.
Min. distance to the medium
If the min. distance to the medium is not main-
tained, the instruments show wrong meas-
ured values. Mount the instrument at the
required min. distance.
Sensor too close to the vessel wall
Sensor too close to the vessel wall
Correct Wrong
Strong heat fluctuations
Shield