VEGA VEGASON 54P…56P Profibus PA - Manual (Page 24)

24 VEGASON 54P … 56P
2 m 4 m 6 m 8 m
10 m
20 m
30 m
B
A
max. meas.
distance
Distance from the
transducer to the
vessel wall
Curve 1 (liquids)
Curve 2 (solids)
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 on the product, i.e.
the useful echo. Please ensure a sufficient
distance from the sensor to the vessel wall
depending on the maximum measuring dis-
tance (dimension B in diagram). In case of
good reflecting conditions (liquids, no vessel
installations), we recommend determining the
sensor distance according to
Diagram curve
1 . At a max. measuring distance of e.g. 10 m,
the distance of the transducer (acc. to curve
1) should be approx. 1.5 m. In case of solids
with poor reflective properties, determine the
distance to the vessel wall according to
Dia-
gram curve 2 . Under very bad measuring
conditions (rough vessel walls, struts), it
might be necessary to increase the distance
to the vessel wall, or to also filter out the false
echoes by storing them in memory, thereby
adapting the sensor more precisely to the
environment.
Mounting and installation
Strong temperature fluctuations
Strong temperature fluctuations, e.g. caused
by 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 vessel wall
Sensor too close to the vessel wall
Correct Incorrect
Strong heat fluctuations
Sun shield