Ohmart Vega VEGAPULS 67, Product Information

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1 D escription of the measuring principle
M easuring principle
E xtremely short microwave pulses with low emitted power are
transmitted by the antenna system to the measured product , re -
fl ected by the product surface and received back by the antenna
system . R adar waves travel at the speed of light . T he time from
emission to reception of the signals is proportional to the level in
the vessel . A special time stretching procedure ensures reliable
and precise measurement of the extremely short transmission
periods .
T he latest microprocessor technology and the proven software
ECHOFOX select the level echo from among a large number of
false echoes and measure it precisely .
B y simply entering the vessel dimensions , a level - proportional
signal is generated out of the distance . F illing the vessel is not
necessary for the adjustment .
W ide application range
VEGAPULS 67 and 68 radar sensors are particularly suitable for
level measurement of bulk solids . T he mechanical construction
as well as the electronics were optimized for this application .
T hrough the special horn and parabolic antennas and the im -
proved dynamic range of the receiver , levels in measuringranges
up to 70 m ( 230 ft ) can be measured . A reliable measurement is
possible with dielectric values from 1 . 6 .
V ersions for real - world applications
A daptable sensors are required for the widely varying product
characteristics and mounting situations . T hat is why VEGAPULS
67 and 68 radar sensors are available with fl ange fi ttings , mount -
ing strap as well as swivelling holder . A n integratedconnectionfor
air rinsing is also available with VEGAPULS 68 . A n optional tem -
perature adapter extends the application range to product tem -
peratures up to 200 ° C ( 392 ° F ). M ounting is very easy and re -
quires no additional work on the measurement loop .
I ndependent of product characteristics
F luctuations in product composition or even complete product
changes do not in fl uence the measuring result . A fresh adjust -
ment is not necessary .
D evice selection
VEGAPULS 67 and 68 radar sensors are available with di ff erent
horn and parabolic antennas . T his yields a variety of instrument -
speci fi c beam angles and measurement characteristics . S elec -
tion of a suitable antenna depends on the respective application .
F or detailed selection you can use the tools " F inder " and " C on -
fi gurator " on our website or contact our respective agency .
1 . 1 A pplication examples
P lastic granules
F ig . 1 : L evel measurement in a plastic granules silo with VEGAPULS 67
P lastic granules and powder are often stored in high , narrow silos
which are fi lled pneumatically . T ypical conditions are fi lling noise ,
material cones and poor re fl ective properties .
T he high sensitivity of the VEGAPULS 67 sensor provides su ffi -
cient power reserves for a reliable level measurement even with
widely varying product surface geometries .
C linker silo
F ig . 2 : L evel measurement in a clinker silo with VEGAPULS 68
C linker is an additive for concrete and is stored in large silos or
bunkers . I ts abrasive properties as well as extreme dust gener -
ation during fi lling place heavy demands on the level measure -
ment .
T he VEGAPULS 68 sensor is the optimum solution for level
measurement . I ts parabolic antenna powerfully focuses the mi -
crowaves , generating a strong useful signal . I nterference from
struts or installations is excluded .
D escription of the measuring principle
4 R adar – L evel measurement of bulk solids
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