AFRISO SonarFox UST 20, Operating Instructions Manual

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19 AFRISO SonarFox UST 20
Before starting the mode it is necessary to empty
the tank as much as possible (preferably comple-
tely).
In case of installed agitator, it is necessary to posi-
tion the agitator under the level meter (direct the
agitator blade to the ultrasonic signal beam).
Note: If there are significant obstacles in the upper
half of the tank, multiple false reflections can occur
especially in closed tanks. In such cases it is ne-
cessary to reduce the level in the tank as much as
possible to correctly mask these possible multiple
false reflections.
1/2 of Tank
obstacles
Tolerance zone for
"LEVEL DISTANCE" value
distance to surface
Fig. 16: Enter value „Set level distance
8 .1 . Service settings
The following points can be set or evaluated in the service setting:
• Length of the electrode
•
Electrode type
• Change or shortening of the electrode
•
Fault conditions of HART®, MODBUS communication
• Default setting
• Reset
BASIC SETTINGS
SERVICE
DIAGNOSTIC
CLONE SETTINGS
PASSWORD
LANGUAGE
INFO
MEDIUM TEMPERATURE
If for instance in the tank there is a difference of 10 °C between the temperature of the measured
material (medium) and the temperature at the mounting site of the level meter (see the mode
"DIAGNOSTICS), the measuring accuracy will be reduced by around 1 % of the set range. If this
function is activated, this temperature difference can be compensated.
Inactive compensation (initial state), the
word "NO" appears on the display.
See the "UNITS" menu for temperature
unit selection (°C or °F).
MEDIUM TEMPERATRE
FAILURE MODE
HART
FACTORY DEFAULT
RESET
Medium Temperature:
YES
+ 20 °C
After start of the zone temperature compensation mode it is necessary to set the temperature of
the surface of the medium. The level meter then calculates the average value from the medium
temperature and the temperature at the installation place of the level meter. With such an average
temperature it counts in calculating of the velocity of acoustic waves propagation and for determi-
nation of the level position.