VEGA VEGAPULS 51K…54K Profibus PA - Manual (Page 21)

VEGAPULS 51P … 54P 21
24890-EN-041227
Mounting and installation
DN 50
ø50
> 500 mm
ø 5...10
VEGAPULS 54: Row of holes in one axis with the type
Type label
Tube antenna system with ball valve cutoff in measur-
ing tube
Ball valve
Vent hole
The more inhomogeneous the measured
product, the closer the openings should be
spaced.
Due to radar signal polarisation, the holes or
slots must be positioned in two rows offset
by 180°.
The radar sensor must then be mounted so
that the type label of the sensor is aligned
with the rows of holes.
Every wider slot causes a false echo. The
slots should therefore not exceed a width of
10 mm in order to keep the signal-to-noise
level at a minimum. Round slot ends are bet-
ter than rectangular ones.
Surge pipe with ball valve
If a ball valve is mounted in the surge pipe,
maintenance and servicing can be carried
out without opening the vessel (e.g. if it con-
tains liquid gas or toxic products).
Deflector
A prerequisite for trouble-free operation is a
ball valve throat that corresponds to the pipe
diameter. The valve must not have rough
edges or constricted areas in its channel.
The distance to the sensor flange should be
at least 500 mm. The seals used should cor-
respond to the tube diameter and should be
conductive.