VEGA VEGAPULS 81 - Manual (Page 37)

VEGAPULS 64 and 81 37
Mounting and installation: Measurements of liquids
Pipe antenna
(surge or bypass pipe)
Pipe antennas are preferably used on vessels
with many installations such as e.g. calorifiers,
heat exchangers or quick stirrers. The meas-
urement of products with strong turbulences,
and installations in the vessel do not cause
false reflections.
By focusing of the radar signal within the
measuring pipe, also products with small
dielectric constants (
ε
r
1,5 … 3) can be meas-
ured.
Pipe antenna system in the tank
Pipe flange system as bypass pipe
Extended bypass pipe
Surge hole
Type
plate
max.
min.
Surge pipe
welded to the
tank
Surge pipe in the
socket piece
100 %
0 %
Casting nose
50 %
0 %
100 %
The surge pipes which open at the bottom
must reach the requested min. level as a
measurement is only possible in the pipe.
Note the upper required ventilation hole in the
surge pipe. These ventilation and surge holes
must be in one axis with the type plate
(VEGAPULS 64) or the casting nose
(VEGAPULS 81).
As an alternative to the surge pipe in the ves-
sel, a pipe antenna outside the vessel is possi-
ble as a bypass pipe.
Note that with the measurement in a pipe, the
max. measuring range is slightly reduced (see
Technical Data).