VEGA VEGAPULS 56 Profibus PA - Manual (Page 31)

VEGAPULS 56 Profibus PA 31
Mounting and installation
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0 %
~45˚
ш 100,8
0,0…0,4
1,5…2
3,6
0,0…0,4
150…500
5…15
3,6
ш 96
2
100 %
Flange DN 100
Smooth welding
neck flange
Connecting
sleeve
Welding neck
flanges
Welding of the plain
welded flange
Welding of the welding
neck flange
Meas. pipe
fastening
Vessel bottom
Deflector
The illustration on the left shows the construc-
tional features of a measuring pipe as exem-
plified by a sensor with DN 100 flange.
Radar sensors with flanges DN 80,
DN 100 and DN 150 are equipped with a
horn antenna. With these sensors, a plain
welded flange can also be used on the sen-
sor end instead of a welding neck flange.
If the vessel contains agitated products,
fasten the measuring pipe to the vessel bot-
tom. Provide additional fastenings for longer
measuring pipes.
A deflector at the bottom end of the measur-
ing pipe scatters the radar signals. In nearly
empty vessels and products with low dielec-
tric value, the deflector ensures that the
product surface is detected rather than the
vessel bottom. Products with low dielectric
constants are partially penetrated, allowing
the vessel bottom to produce (when the
product level is low) a considerably stronger
radar echo than the product surface.
With the deflector, however, only the useful
signal is received in a nearly empty vessel -
the 0 % level is reliably detected and the
correct measured value transmitted.
Rz
≤
30
Deburr the
holes
Min. product
level to be
measured
(0 %)