VEGA VEGAPULS 54K enamel - Manual (Page 5)

VEGAPULS 54K enamel 5
24 101-EN-041227
Product description
Reflected radar power dependent on the dielectric
constant of the measured product
2
0
0
10
25 %
40 %
5
10
5 %
20
30
40
50
%
4 6 8 12 14 16 18
20
ε
r
Hence, it is possible for the VEGAPULS 50
radar sensors to process the slow-motion
pictures of the sensor environment precisely
and in detail in cycles of 0.5 to 1 second
without using time-consuming frequency
analysis (e.g. FMCW, required by other radar
techniques).
Nearly all products can be measured
Radar signals display physical properties
similar to those of visible light. According to
the quantum theory, they propagate through
empty space. Hence, they are not depend-
ent on a conductive medium (air), and they
spread out like light at the speed of light.
Radar signals react to two basic electrical
properties:
- the electrical conductivity of a substance
- the dielectric constant of a substance.
All products which are electrically conductive
reflect radar signals very well. Even slightly
conductive products provide a sufficiently
strong reflection for a reliable measurement.
All products with a dielectric constant
ε
r
greater than 2.0 reflect radar pulses suffi-
ciently (note: air has a dielectric constant
ε
r
of
1).
t t
1 ns
278 ns
Time transformation
Pulse sequence
Puls
Pulse
break
VEGAPULS can achieve this through a spe-
cial time transformation procedure which
spreads out the more than 3.6 million echo
images per second in a slow-motion picture,
then freezes and processes them.
Signal reflectivity grows stronger with in-
creasing conductivity or increasing dielectric
constant of the product. Hence, nearly all
substances can be measured.
As process fitting, standard flanges of DN
150, DN 200, ANSI 6“ or ANSI 8“ are used.
Due to high quality enamel coating, the sen-
sors withstand even extreme chemical and
physical conditions. The sensors deliver
stable, reproducible analogue or digital level
signals with reliability and precision, and
have a long useful life.