Siemens SITRANS Probe LU Quick Start Manual page 13

6. Set measurement range (P007: Span)
Range
Values
Default
.
Notes:
• Setting P006 resets Span, if it has not previously been set to a different value.
• The default setting for Span is based on Operation (P001) and Empty (P006). Span is set to
Empty minus 110% of Blanking distance
this case, Span is set to Empty distance.
• Always prevent the monitored surface from approaching within 0.3 m (1 ft) of the
transducer face. This provides a 0.05 m (2") safety margin, as 0.25 m (10") is the minimum
distance detectable.
7. Minimize false reflections: Set P838 (Auto False Echo Suppression Distance)
Use P838 and P837
together: follow the
instructions for P837.
8. Enable False Echo Suppression: set P837 (Auto False Echo Suppression)
Off
0
Use "learned" TVT
Value 1 *
"Learn"
2
Using P837 and P838 (perform this function at low tank levels)
The TVT (Time Varying Threshold) curve sets a threshold which screens out false echoes
SITRANS Probe LU displays an incorrect full level, or if the reading fluctuates between a false
high level and a correct level, use P838 and P837 together to elevate the TVT (Time Varying
Threshold) in this region and de-sensitize the receiver from any 'base noise' caused by internal
transducer reflections, nozzle echoes, or other vessel false echoes
1.
Default setting for Blanking is 0.25 m (10").
2.
False echoes can be caused by obstructions in the beam path.
3.
For more details on Auto False Echo Suppression, please see the full manual.
7ML19985QR81
1
0.0000 to 6.000 m (20 ft) or
0.0000 to 12.000 m (40 ft)
5.725 m (18.78 ft) or
11.725 m (38.47 ft)
1
, unless Operation is set to distance (P001=3). In
Range
(depends on model)
Value
Default
SITRANS Probe LU – QUICK START MANUAL
Span can be set at any distance above
Empty level
Maximum range:
0.000 to 6.000 m (20 ft) or
0.000 to 12 m (40 ft)
1.000 m (3.28 ft)
3 .
2
. If
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