P800 Near Blanking; P801 Range Extension; P804 Confidence Threshold - Siemens SITRANS L Series Operating Instructions Manual

Parameter assignment
7.25 Echo processing (P800 to P807)
7.25.1

P800 Near blanking

Defines the distance from the reference point to be ignored by the transmitter/receiver.
Values
Related parameters
To extend the blanking beyond the minimum default, enter a value in units.
7.25.2

P801 Range extension

Note
Maximum range extension depends on the setting for P006 (Empty).
Allows the material level to drop below Empty (process empty level), without generating an
LOE state.
Values
Related parameters
Use this feature if the surface monitored can drop below Empty level (P006) in normal
operation. The value for P801 is added to Empty, and the sum can be greater than the range
of the antenna. Range Extension can be increased (in Units or percent of Span) to a point
where Empty plus Range Extension is greater than the distance from the flange face to the
furthest surface to be monitored. The distance below empty is not blanked.
● Enter the value as a percentage of P006.
● For vessels with conical or parabolic bottoms, increase the value for P801 to ensure that
an empty vessel reads Empty.
7.25.3

P804 Confidence threshold

Determines which echoes are evaluated by software.
Values
Related parameters
P804 sets the minimum echo confidence that the echo must meet in order to prevent a Loss
of Echo condition and the expiration of the Failsafe timer (P070). When Echo Confidence
(P805) exceeds the Confidence Threshold, the echo is evaluated.
64
Range
Default
P006 Empty
P007 Span
P838 Auto False-Echo Suppression Distance
Range
Default
P006 Empty
P007 Span
Range
Default
P070 Failsafe timer
0.00 to 20 (m: selected in P005)
0.30 m (plus the shield length)
0 to 1000%
5.000 (% of Span)
0 to 99
5
SITRANS Probe LR with mA/HART
Operating Instructions, 05/2019, A5E32337711-AC