Siemens SITRANS LUT400 Operating Instructions Manual page 191

2.12.2.2. Echo Threshold
Sets the minimum echo confidence that the echo must meet in order to
prevent a Loss of Echo condition and the expiration of the Fail-safe (LOE)
timer. When Confidence (3.2.9.2.) exceeds Echo Threshold (2.12.2.2.), the
echo is accepted as a valid echo and is evaluated.
Values
Use this feature when an incorrect material level is reported.
2.12.2.3. Reform Echo
Smooth jagged peaks in the echo profile.
Values
a.
Use this feature when monitoring solids if the reported level fluctuates
slightly though the monitored surface is still. Enter the amount (in ms) of
Echo Profile smoothing required. When a value is keyed in, the nearest
acceptable value is entered.
2.12.2.4. Narrow Echo Filter
Filters out echoes of a specific width.
Values
a.
Use this for transducer acoustic beam interference (e.g. ladder rungs).
Enter the width of false echoes (in groups of 25 ms), to be removed from
the Echo Profile. [For example, select value of 3 to remove 75 ms (3 x 25
ms) of false echos from the profile.]
When a value is keyed in, the nearest acceptable value is entered.
2.12.2.5. Submergence Detection
Enables/disables submergence detection.
Values
(Submergence Detection Shield must first be installed on transducer.)
When this parameter is enabled and the transducer becomes submerged:
• fault code 26 is displayed (see General Fault Codes on page 233),
• mA output immediately advances to Minimum mA Limit (2.5.5.) orMaxi-
• DISTANCE is set to zero (corresponding to a high level),
• pumps and alarms operate normally (according to level), therefore they
A5E33329501 SITRANS LUT400 (HART) – OPERATING INSTRUCTIONS
Range: -20 to 128
Default: 5
Range: 0 to 50 intervals
Default: 0
one interval = span of 24.5 micro seconds
Range: 0 to 14 intervals
Default: 2
one interval = span of 24.5 micro seconds
*
mum mA Limit (2.5.6.), as defined by the application,
remain ON (or activate if not already ON).
a
(greater = wider)
a
(greater = wider)
Enabled
Disabled
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