8
3 Mounting
VEGAFLEX 81 • Foundation Fieldbus
47589-EN-140324
Plastic vessel/Glass vessel
The guided microwave principle requires a metallic surface on the
process fitting. Therefore, in plastic vessels, etc., use an instru
-
ment version with flange (from DN 50) or place a metal sheet
(ø > 200 mm/8 in) beneath the process fitting when screwing it in.
Make sure that the plate has direct contact with the process fitting.
When installing rod or cable probes in vessels without metal walls,
e.g. in plastic vessels, the measured value can be influenced by
strong electromagnetic fields (emitted interference according to
EN 61326: class A). In this case, use a probe with coaxial version.
1
2
Fig. 3: Installation in non-metallic vessel
1 Flange
2 Metal sheet
If possible, avoid sockets. Mount the sensor flush with the vessel top.
If this is not possible, use short sockets with small diameter.
Higher sockets or sockets with a bigger diameter can generally be
used. They can, however, increase the upper blocking distance (dead
band). Check if this is relevant for your measurement.
In such cases, always carry out a false signal suppression after instal-
lation. You can find further information under "
Setup procedure
".
Type of vessel
Socket
