Vega VEGASON 61 Operating Instructions Manual page 17

Inflowing medium
Foam
Air turbulences
VEGASON 61 • Four-wire 4 ... 20 mA/HART
Fig. 12: Agitators
Do not mount the instruments in or above the filling stream. Make sure
that you detect the medium surface, not the inflowing product.
Fig. 13: Inflowing liquid
Through the action of filling, stirring and other processes in the vessel,
dense foams which considerably damp the emitted signals may form
on the medium surface.
If foams are causing measurement errors, the sensor should be used
in a standpipe or, alternatively, the more suitable guided radar sen-
sors (TDR) should be used.
Guided wave radar is unaffected by foam generation and is particu-
larly suitable for such applications.
If there are strong air currents in the vessel, e.g. due to strong winds
in outdoor installations or air turbulence, e.g. by cyclone extraction
you should mount VEGASON 61 in a standpipe or use a different
measuring principle, e.g. radar or guided radar (TDR).
4 Mounting
17