Dinel ULM-53 series, Instruction Manual

9

© 

Dinel, s.r.o.      UL_–53

• 

The ultrasonic signal can be scattered or attenuated if the 

surface is moderately stirred or rippled (due to a mixer, inflow 

of liquid, etc.). This may result in 

reduction of the measure-

ment range

 or unreliable operation of the device (Fig. 11). 

For a rippled or swirling level, you can use the directional 

horn to eliminate scattering of the ultrasonic signal.

!

Fig. 11: Moderately stirred surface

• 

The site for installing the level meter needs to be chosen so that the emitted acoustic signal is not 

affected by 

nearby objects

 (reinforcements, supports, brackets, ladders, heating elements, mixers, 

etc.). These obstacles may result in false rebounds, increasing measurement inaccuracy (Fig. 9).

x  –  distance from the edge of the longest  

  object
c  –  maximum reach of the level meter

UL_–53–01 ;02 ; 10

x > c/12

(min. 200 mm)

UL_–53–06

x > c/8

(min. 200 mm)

UL_–53–20

x > c/10

(min. 200 mm)

Fig. 9: Minimum distance from close objects in the tank

• 

Foam may be produced on the surface of the measured liquid 

during filling, mixing and other processes. The thick foam 

significantly absorbs the ultrasound signal and may cause 

malfunction of the device (Fig.10). In those cases it is neces-

sary to test the device in advance or contact the manufacturer .  

In case of a thin layer of foam, it is also possible to use 

directional horn for improving receipt of the reflected echo.  

!

Fig. 10: Thick foam on the surface

!

Fig. 12: Strongly stirred 

surface

Fig. 13: False reflection from 

mixer blades

• 

The device should not be installed in places 

with the risk of 

false reflections

 of the ultra-

sonic signal from the mixer’s blades (Fig. 13).

•  False  surface  reflections  of  the  ultrasonic 

signal and unreliable operation of the device 

might result from the mixer’s 

rotating blades

that ripple the surface level(Fig. 12).