ULM–70
©
Dinel, s.r.o.
7
Fig. 13: Intensely stirred surface
!
Fig. 10: Prevention to avoid intrusion of
humidity
Fig. 9: Solar radiation shielding cover
• The level meter must not be installed in places
with direct
solar radiation
and must be protected
against weather effects.
• If the installation in places with direct solar radia-
tion is inevitable, it is necessary to mount a
shield-
ing cover
above the level meter.
• It is suitable to run the cable under a cable bush-
ing (obliquely down in slack) according to Fig. 10
to prevent
penetration of humidity
. Then the rain
and condensing water can flow off freely.
• The cable bushing and connector have to be
suf-
ficiently tightened
to prevent penetration of hu-
midity.
• To lower the minimum distance to the measured
medium,
a reflection board
made from solid,
even and smooth material can be installed to the
level meter. Then the tank can be filled nearly up
to the maximum height. The solution is suitable for
open tanks and reservoirs.
• Scattering or attenuation of the ultrasonic signal
can result if the surface level has been
moder-
ately stirred
or
rippled
(by a mixer, coming liq-
uid etc.). It can result in reduction of the meas-
urement range or unreliable function of the level
meter (Fig. 12).
• Rotating
mixer blades
can cause that the surface
is stirred, which results in false reflections of the
ultrasonic signal from the surface level and unreli-
able operation of the level meter (Fig. 13).
Fig. 12: Moderately stirred surface
Fig. 11: Reflection board
H + L = Dead zone
(blind zone, blocking dist.)
