VEGA VEGASON 54P…56P Profibus PA - Manual (Page 21)

VEGASON 54P … 56P 21
Mounting and installation
Max. socket length in relation to socket
diameter
ø in mm L in mm
Type 54
Type 55 Type 56
200 400 – – – –
250 500 500 500
300 – – – – 600
Socket extension in solids
For solids, use a conical socket extension
with a taper of at least 15° … 20°.
Socket extensions not immersed into the medium
ø
45˚
L
ø
45˚
L
Type 54 Type 55
Socket extension in solids
15˚ 15˚
2.6 False echoes
The mounting location of the ultrasonic sensor
must be selected such that no installations or
inflowing material are in the path of the ultra-
sonic impulses. The following examples and
instructions show the most frequent measur-
ing problems and how to avoid them.
Vessel protrusions
Vessel forms with flat protrusions can, due to
their strong false echoes, adversely effect
the measurement. Shields above these flat
protrusions scatter the false echoes and
guarantee a reliable measurement.
Intake pipes, e.g. for the mixing of materials,
with a flat surface directed towards the sen-
sor should be covered with a sloping shield.
The shield will scatter the false echo.
Vessel protrusions (intake pipe)
Correct Incorrect
Vessel protrusions (slope)
Correct Incorrect
The socket diameter should be as large and
the socket length as small as possible. To
minimise false echoes, make sure that the
socket outlet is burr-free.