Vega VEGASON 61 Operating Instructions Manual page 32

6 Set up with the display and adjustment module PLICSCOM
Diagnosis - Measurement
reliability
Diagnostics - Device
status
Diagnosis - Curve selec-
tion
Diagnosis - Curve pres-
entation
32
Peak value indicator
When non-contact level sensors are used, the measurement can be
influenced by the respective process conditions. In this menu item,
the measurement reliability of the level echo is displayed as a dB
value. Measurement reliability equals signal strength minus noise. The
higher the value, the more reliable the measurement. A well function-
ing measurement normally has a value > 10 dB.
The instrument status is displayed in this menu item. If no failure is
detected by the sensor, " OK" will be displayed. If a failure is detected,
there will be a sensor-specific flashing fault signal, for example "
E013". The failure is also displayed in clear text, for example " No
measured value available".
Information:
The fault message as well as the clear text indication are also carried
out in the measured value display.
Measurement reliability
Device status
With ultrasonic sensors, the " Echo curve" represents the signal
strength of the echoes over the measuring range. The unit of signal
strength is "dB". The signal strength enables the jusgement of the
quality of the measurement.
The " False echo curve" displays the saved false echoes (see menu
" Service") of the empty vessel as signal strength in "dB" over the
measuring range.
Up to 3000 measured values are recorded (depending on the sensor)
when starting a " Trend curve". Then the values can be displayed on
a time axis. The oldest measured values are always deleted.
In the menu item " Choose curve", the respective curve is selected.
Curve selection
►
Echo curve
Information:
The trend recording is not activated when being shipped. It must be
started by the user via the menu item " Start trend curve".
A comparison of the echo curve and the false echo curve allows a
more detailled evaluation of measurement reliability. The selected
curve is updated continuously. With the [OK] key, a submenu with
zoom functions is opened.
VEGASON 61 • Four-wire 4 ... 20 mA/HART