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6 Set up with the display and adjustment module
VEGAPULS 65 • Foundation Fieldbus
36518-EN-140209
The "
Echo curve
" shows the signal strength of the echoes over the
measuring range in dB. The signal strength enables an evaluation of
the quality of the measurement.
The "
False signal suppression
" displays the saved false echoes (see
menu "
Additional settings
") of the empty vessel with signal strength in
"dB" over the measuring range.
A comparison of echo curve and false signal suppression allows a
more detailed statement of the reliability.
The selected curve is permanently updated. A submenu with zoom
functions is opened with the
[OK]
key:
•
"X-Zoom": Zoom function for the meas. distance
•
"Y-Zoom": 1, 2, 5 and 10x signal magnification in "
dB
"
•
"Unzoom": Reset the presentation to the nominal measuring range
with single magnification
With the function "
Echo curve memory
" the echo curve can be saved
at the time of setup. This is generally recommended; for using the As
-
set Management functions it is absolutely necessary. If possible, the
curve should be saved with a low level in the vessel.
With the adjustment software PACTware and the PC, the high resolu
-
tion echo curve can be displayed and used to recognize signal
changes over the operating time. In addition, the echo curve of the
setup can be also displayed in the echo curve window and compared
with the actual echo curve.
The following circumstances cause interfering reflections and can
influence the measurement:
•
High sockets
•
Vessel installations such as struts
•
Agitators
•
Buildup or welded joints on vessel walls
Diagnoses - Curve indica-
tion
Diagnostics - Echo curve
memory
Additional adjustments -
False signal suppression
