Emerson 3308A Rosemount 3308 Series, Reference Manual

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Reference Manual
00809-0100-4308, Rev BA
Appendix D: Configuration Parameters
December 2014
Configuration Parameters
D.3.5 Echo Tuning
Thresholds
Figure D-6. Thresholds
Threshold Control Thresholds can be automatically calculated by device or
manually set by user. This setting is valid for all thresholds on
the Thresholds tab (Surface, Interface Reference, and Probe
End Thresholds).
Surface Threshold Threshold to filter out noise in the echo curve for detection of
the Surface. Noise below the threshold is suppressed. The
first echo peak closest to the device that crosses and is above
the Surface Threshold is the surface echo.
Interface Threshold Threshold to filter out noise in the echo curve for detection of
the Interface. The first echo peak after the surface echo that
crosses and is above the Interface Threshold is the interface
echo.
Reference Threshold Threshold to filter out noise in the echo curve for detection of
the Reference peak. The reference peak is a strong negative
echo very close to the device.
Probe End Threshold Threshold to filter out noise in the echo curve for detection of
the Probe End peak. The probe end peak is a fairly strong
positive or negative echo (depending on probe type) that is
present at the probe end when tank is empty.
DISTANCE
AM
PLI
T
UDE
Interface Threshold
Surface Threshold
Probe End Threshold
Reference Threshold