VEGA VEGAPULS 66 (≥ 2.0.0 - ≥ 4.0.0) 4 … 20 mA_HART - four-wire - Manual (Page 18)

18
4 Mounting
VEGAPULS 66 • 4 … 20 mA/HART - four-wire
36520-EN-121011
Fig. 13: Agitators
Through the action of filling, stirring and other processes in the vessel,
dense foams which considerably damp the emitted signals may form
on the product surface.
If foams are causing measurement errors, the biggest possible radar
antenna should be used.
As an alternative, sensors with guided microwave can be used. These
are unaffected by foam generation and are best suited for such ap-
plications.
When using a surge pipe in a vessel, influences from vessel installa-
tions and turbulences can be excluded. Under these prerequisites,
the measurement of products with low dielectric values (ε
r
value
≥ 1.6) is possible. In very adhesive products, measurement in a surge
pipe is not recommended.
Foam generation
Measurement in a surge
pipe