Emerson Rosemount 3308 Series Reference Manual page 219

Reference Manual
00809-0100-4308
D.2.5 Echo tuning
Thresholds
Figure D-10: Thresholds
A. Amplitude
B. Distance
C. Reference Threshold
D. Surface Threshold
E. Interface Threshold
F. Probe End Threshold
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.
Reference Manual
Configuration parameters
February 2020
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