VEGA VEGASON 54P…56P Profibus PA - Manual (Page 22)

22 VEGASON 54P … 56P
Buildup
If the sensor is mounted too close to the
vessel wall, residues or buildup of the meas-
ured product on the vessel wall can cause
false echoes. Position the sensor at a suffi-
cient distance from the vessel wall. Please
also note chapter "2.2 General installation
instructions".
Inflowing material
Do not mount the instrument in or above the
filling stream. Ensure that you detect the
product surface and not the inflowing mate-
rial.
Mounting and installation
Vessel installations
Vessel installations such as, for example, a
ladder, often cause false echoes. Make sure
when planning your measurement loop that
the ultrasonic signals have free access to the
measured product.
Vessel installations
Correct Incorrect
Ladder
Ladder
Struts
Struts, like other vessel installations, can
cause strong false echoes that are superim-
posed over the useful echo signal. Small
shields effectively hinder a direct false echo
reflection. The false echoes are scattered
and diffused in the area and are then filtered
out as "echo noise" by the measuring elec-
tronics.
Struts
Correct Incorrect
Shields
Inflowing material
Correct Incorrect
Correct Incorrect