VEGA VEGAPULS 56 Profibus PA - Manual (Page 22)

22 VEGAPULS 56 Profibus PA
;;
;;
;;
;;
;;
;;
;;
;;
;;
;;
;;
;;
;;
;;
;;
;;
;;
;;
;;
Measuring range (operating range) and max. measuring distance
Note: Use of the sensors for applications with solids is limited.
full
Meas. range
max. meas. distance 20 m
3 Mounting and installation
3.1 General installation instructions
Measuring range
The reference plane for the measuring range
of the sensors is the lower edge of the flange.
The measuring range is 0 … 20 m. For meas-
urement in surge or bypass tubes (pipe
antenna) the max. measuring distance is
reduced (see "Technical data - Measuring
range“).
Keep in mind that in measuring environments
where the medium can reach the sensor
flange, buildup can form on the antenna
which can cause measurement errors. The
min. distance of the antenna to the medium
should be 5 cm.
Reference plane
empty
Profile with smooth interfering surfaces cause large
false signals
Round profiles diffuse radar signals
A deflector causes signal scattering
Mounting and installation
False reflections
Flat obstructions and struts cause large false
reflections. They reflect the radar signal with
high energy density.
Interfering surfaces with a round profile dif-
fuse the reflected radar signals and cause
false reflections with lower energy density.
Hence, they are less critical than reflections
from a flat surface.
If flat obstructions in the range of the radar
signals cannot be avoided, we recommend
the installation of a deflector plate to scatter
the reflected signals. Due to this scattering,
the interfering signals will be low in amplitude
and so diffuse that they can be filtered out by
the sensor.
min. meas.
distance min. min. meas.
distance
min. meas.
distance
full
empty