VEGA VEGAPULS 51K…54K 4 … 20 mA; HART compact sensor - Manual (Page 20)

20 VEGAPULS 51K … 54K
21750-EN-031222
Mounting and installation
0 %
~45˚
ш 100,8
0,0…0,4
1,5…2
3,6
0,0…0,4 150…500
5…10
3,6
ш 95 2
100 %
Flange
DN 100
Connecting
sleeve
Welding neck
flanges
Welding of the smooth
welding neck flanges
Welding of the connect-
ing sleeves
Meas. pipe fastening
Vessel
bottom
Deflector
Deburr the
holes
Welding of the welding
neck flanges
0 %
0 %
Quadrant pipe on the bypass tube end
Quadrant pipe on the standpipe end
In products with lower dielectric values (< 4),
a part of the radar signal penetrates the
medium. If the vessel is nearly empty, echoes
are generated by both the product and the
vessel bottom. The echo from the vessel
bottom can in some cases be stronger than
the echo from the product surface. If a de-
flector is installed below the open end of the
measuring tube, the radar signals are scat-
tered and prevented from reaching the ves-
sel bottom. This ensures that, in nearly empty
vessels or with products of low dielectric
value, the product delivers a more distinct
echo than the vessel bottom.
Due to the deflector, the useful echo (and
thus the measured value) remains clearly
detectable in a nearly empty vessel, and the
0 % level can be reliably measured.
The standpipe or surge pipe can be
equipped with a quadrant pipe at its end
instead of a deflector. This quadrant pipe
reflects the radar signals that penetrate the
medium diffusely to the side and diminishes
strong echoes from the tube end or the ves-
sel bottom.
VEGAPULS 54