Emerson Rosemount 3308 Series Reference Manual page 123

Reference Manual
00809-0100-4308
Related information
Read the echo curve
Guidelines for setting the amplitude thresholds
Restore default thresholds
Procedure
1. Select Service Tools → Echo Tuning → Thresholds.
2. Under Threshold Control, select Default (Automatic), and then select Send.
Example 1: Product surface peak not found
If the transmitter does not track the product surface correctly, it may be necessary to
adjust the threshold values. In
the product level will not be detected. In a situation like this, the Surface Threshold has to
be lowered so that the surface peak is not filtered out.
Figure 6-3: Surface Threshold Is Too High
A. Amplitude
B. Distance
C. Surface Threshold is above the Product Surface peak.
If there are disturbing objects in the tank, the Surface Threshold must be carefully set to
avoid locking on the wrong amplitude peak. In
low, and as a result the transmitter has locked on a peak above the actual product surface.
A disturbance was interpreted as the product surface, since this was the first amplitude
peak closest to device that went above Surface Threshold. The actual product surface was
interpreted as the interface or the probe end.
Reference Manual
d) Select desired Threshold to adjust, type the new value into the box, and then
select Send.
Figure
Service and troubleshooting
6-3, the Surface Threshold is too high and as a result
Figure 6-4, the Surface Threshold is too
February 2020
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